STABLE VALUE SEPARATE ACCOUNT (Details) - North America 401(k) Savings Plan - USD ($)	12 Months Ended
Dec. 31, 2025	Dec. 31, 2024
STABLE VALUE SEPARATE ACCOUNT
Stable value investment at contract value	$ 945,584,172	$ 980,609,332
Number of business days to cure contract breach before Plan's ability to conduct transactions is limited	15 days
MassMutual Stable Value Separate Account
STABLE VALUE SEPARATE ACCOUNT
Crediting interest rates	0.51%	3.70%
Stable value investment at contract value	$ 0	$ 980,609,332
Fresenius Stable Value Separate Accounts
STABLE VALUE SEPARATE ACCOUNT
Stable value investment at contract value	$ 945,584,172
Fresenius Stable Value Separate Accounts \| Minimum
STABLE VALUE SEPARATE ACCOUNT
Crediting interest rates	0.00%

Represent the credit interest rate of an investment in an underlying guaranteed investment contract.

No definition available.

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- Definition

Represents the period within which the company must cure the breach of guaranteed investment contract .

+ References

No definition available.

+ Details

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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/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478416/962-205-50-1

+ Details

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Period Type:	duration

- Definition

Contract value of investment, excluding plan interest in master trust, held by employee stock purchase, saving, or similar plan (employee benefit plan (EBP)). Includes, but is not limited to, insurance contract meeting fully benefit-responsive investment criteria.

+ References

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 55
-Paragraph 17
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478873/962-325-55-17

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-05(a)(Schedule II))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 325
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477783/962-325-50-3

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-03(3))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

Reference 5: http://www.xbrl.org/2003/role/disclosureRef
-Topic 962
-SubTopic 205
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.6A-02(d))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477804/962-205-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Details

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- Details

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- Details

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- Details

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