Significant accounting policies (Details)	12 Months Ended
Dec. 31, 2025 USD ($)
Property, Plant and Equipment [Line Items]
Number of contractual days past due after which credit card consumer loans are generally written off	180 days
Outstanding balance threshold under which consumer loans are generally written off	$ 100,000
Number of contractual days past due after which consumer loans under $100,000 are generally written off	180 days
Buildings
Property, Plant and Equipment [Line Items]
Useful life	50 years
Equipment \| Minimum
Property, Plant and Equipment [Line Items]
Useful life	3 years
Equipment \| Maximum
Property, Plant and Equipment [Line Items]
Useful life	10 years
Software and Software Development Costs \| Minimum
Property, Plant and Equipment [Line Items]
Useful life	5 years
Software and Software Development Costs \| Maximum
Property, Plant and Equipment [Line Items]
Useful life	10 years
Other Intangible Assets \| Maximum
Property, Plant and Equipment [Line Items]
Other acquired intangible assets, useful life (not exceeding)	15 years

Threshold Contractual Days Past Due, Credit Card Consumer Loans

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Threshold Contractual Days Past Due, Consumer Loans, Balance Under $100,000

+ References

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Threshold Outstanding Balance, Consumer Loans

+ References

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- Definition

Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 842
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 7A
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478964/842-20-50-7A

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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

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