Employee benefit plans - Plan Assets (Details) - Plan assets - EUR (€) € in Thousands	Dec. 31, 2025	Dec. 31, 2024
Fair values
Plan assets	€ 263,607	€ 259,832
Equity investments
Fair values
Index funds		73,272
Fixed income investments
Fair values
Government securities		190
Corporate bonds		171,860
Other bonds		6,668
U.S. treasury money market funds	60,741	3,619
Other types of investments
Fair values
Cash, money market and mutual funds	73	4,223
Annuity buy-in contract	202,793
Level 1
Fair values
Plan assets	60,814	13,294
Level 1 \| Equity investments
Fair values
Index funds		9,570
Level 1 \| Fixed income investments
Fair values
Government securities		19
U.S. treasury money market funds	60,741	3,619
Level 1 \| Other types of investments
Fair values
Cash, money market and mutual funds	73	86
Level 2
Fair values
Plan assets		240,201
Level 2 \| Equity investments
Fair values
Index funds		63,702
Level 2 \| Fixed income investments
Fair values
Government securities		171
Corporate bonds		171,860
Other bonds		331
Level 2 \| Other types of investments
Fair values
Cash, money market and mutual funds		4,137
Level 3
Fair values
Plan assets	202,793	6,337
Level 3 \| Fixed income investments
Fair values
Other bonds		€ 6,337
Level 3 \| Other types of investments
Fair values
Annuity buy-in contract	€ 202,793

The amount that cash, money market, and mutual funds constitute of the fair value of defined benefit plan assets.

No definition available.

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- Definition

The amount that corporate bonds constitute of the fair value of defined benefit plan assets.

+ References

No definition available.

+ Details

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- Definition

The amount that government securities constitute of the fair value of defined benefit plan assets.

+ References

No definition available.

+ Details

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- Definition

The amount that index funds constitute of the fair value of defined benefit plan assets.

+ References

No definition available.

+ Details

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- Definition

The amount that money market funds constitute of the fair value of defined benefit plan assets.

+ References

No definition available.

+ Details

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- Definition

The amount that other bonds equivalents constitute of the fair value of defined benefit plan assets.

+ References

No definition available.

+ Details

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- Definition

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

+ References

No definition available.

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- Definition

The fair value of defined benefit plan assets. Plan assets comprise assets held by a long-term employee benefit fund and qualifying insurance policies. [Refer: At fair value [member]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

The amount qualifying insurance policies contribute to the fair value of defined benefit plan assets. [Refer: Plan assets, at fair value; Defined benefit plans [domain]]

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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