Face (par) amount of debt instrument at time of issuance.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482949/835-30-55-8

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

Reference 3: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69B
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69B

Reference 4: http://www.xbrl.org/2003/role/exampleRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 55
-Paragraph 69C
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481568/470-20-55-69C

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

Reference 6: http://www.xbrl.org/2003/role/disclosureRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

+ Details

Name:	us-gaap_DebtInstrumentFaceAmount
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22)(a)(1))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1B
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1B

+ Details

Name:	us-gaap_DebtInstrumentInterestRateStatedPercentage
Namespace Prefix:	us-gaap_
Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt discount (premium).

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 1A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-1A

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482925/835-30-45-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 835
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482900/835-30-50-1

Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 470
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1D
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481139/470-20-50-1D

+ Details

Name:	us-gaap_DebtInstrumentUnamortizedDiscountPremiumNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

+ References

+ Details

Name:	us-gaap_DeferredFinanceCostsNet
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash outflow to repay long-term debt that is not secured by collateral. Excludes repayments of tax exempt unsecured debt.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 230
-SubTopic 10
-Name Accounting Standards Codification
-Section 45
-Paragraph 15
-Subparagraph (b)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-15

+ Details

Name:	us-gaap_RepaymentsOfUnsecuredDebt
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- References

No definition available.

+ Details

Name:	us-gaap_SeniorLongtermNotesCurrentAndNoncurrentAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

Principal Amount Of Debt Outstanding

+ References

No definition available.

+ Details

Name:	wpc_PrincipalAmountOfDebtOutstanding
Namespace Prefix:	wpc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Principal Amount Of Debt Repaid

+ References

No definition available.

+ Details

Name:	wpc_PrincipalAmountOfDebtRepaid
Namespace Prefix:	wpc_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

Debt - Senior Unsecured Notes (Details)	1 Months Ended
Debt - Senior Unsecured Notes (Details)	Jul. 31, 2024 EUR (€)	Apr. 30, 2024 USD ($)	Jul. 24, 2024	Jun. 30, 2024 USD ($)	Jun. 30, 2024 EUR (€)	Jun. 28, 2024 USD ($)	May 16, 2024 EUR (€)	Dec. 31, 2023 USD ($)
Senior Unsecured Notes
Unamortized deferred financing costs				$ 28,548,000
Unamortized discount, net				35,570,000
Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)		4.60%
Principal Amount				6,600,000,000
Principal amount of debt outstanding				6,573,513,000				$ 6,076,875,000
Unamortized deferred financing costs				28,000,000.0				21,100,000
Unamortized discount, net				$ 25,600,000				20,100,000
Repayment of unsecured debt		$ 500,000,000
Unsecured Senior Notes \| Subsequent Events
Senior Unsecured Notes
Coupon rate (as a percent)	2.25%		2.25%
Repayment of unsecured debt \| €	€ 500,000,000
Principal amount of debt repaid \| €	€ 500,000,000
4.6% Senior Notes due 2024 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				4.60%	4.60%
Principal Amount				$ 500,000,000
Principal amount of debt outstanding				$ 0				500,000,000
2.25% Senior Notes due 2024 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				2.25%	2.25%
Principal Amount \| €					€ 500,000,000
Principal amount of debt outstanding				$ 535,250,000				552,500,000
4.0% Senior Notes due 2025 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				4.00%	4.00%
Principal Amount				$ 450,000,000
Principal amount of debt outstanding				$ 450,000,000				450,000,000
2.25% Senior Notes due 2026 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				2.25%	2.25%
Principal Amount \| €					€ 500,000,000
Principal amount of debt outstanding				$ 535,250,000				552,500,000
4.25% Senior Notes due 2026 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				4.25%	4.25%
Principal Amount				$ 350,000,000
Principal amount of debt outstanding				$ 350,000,000				350,000,000
2.125% Senior Notes due 2027 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				2.125%	2.125%
Principal Amount \| €					€ 500,000,000
Principal amount of debt outstanding				$ 535,250,000				552,500,000
1.35% Senior Notes due 2028 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				1.35%	1.35%
Principal Amount \| €					€ 500,000,000
Principal amount of debt outstanding				$ 535,250,000				552,500,000
3.85% Senior Notes due 2029 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				3.85%	3.85%
Principal Amount				$ 325,000,000
Principal amount of debt outstanding				$ 325,000,000				325,000,000
3.41% Senior Notes due 2029 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				3.41%	3.41%
Principal Amount \| €					€ 150,000,000
Principal amount of debt outstanding				$ 160,575,000				165,750,000
0.95% Senior Notes due 2030 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				0.95%	0.95%
Principal Amount \| €					€ 525,000,000
Principal amount of debt outstanding				$ 562,013,000				580,125,000
2.4% Senior Notes due 2031 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				2.40%	2.40%
Principal Amount				$ 500,000,000
Principal amount of debt outstanding				$ 500,000,000				500,000,000
2.45% Senior Notes due 2032 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				2.45%	2.45%
Principal Amount				$ 350,000,000
Principal amount of debt outstanding				$ 350,000,000				350,000,000
4.25% Senior Notes due 2032 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				4.25%	4.25%		4.25%
Principal Amount				$ 650,000,000		$ 400,000,000	€ 650,000,000
Principal amount of debt outstanding				$ 695,825,000				0
3.7% Senior Notes due 2032 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				3.70%	3.70%
Principal Amount \| €					€ 200,000,000
Principal amount of debt outstanding				$ 214,100,000				221,000,000
2.25% Senior Notes due 2033 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				2.25%	2.25%
Principal Amount				$ 425,000,000
Principal amount of debt outstanding				$ 425,000,000				425,000,000
5.375% Senior Notes due 2034 \| Unsecured Senior Notes
Senior Unsecured Notes
Coupon rate (as a percent)				5.375%	5.375%	5.375%
Principal Amount				$ 400,000,000
Principal amount of debt outstanding				$ 400,000,000				$ 0