Fair Value Measurements - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2024	Dec. 31, 2023
Partnerships
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net asset value, redemption restriction period	15 days
Commingled and Common Collective Trust Funds
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Net asset value, redemption restriction period	45 days
2023 Fixed-to-Floating Interest Rate Swaps \| Fair Value Hedging \| Designated as Hedging Instrument
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate fair value hedge asset at fair value	$ 7,000,000	$ 19,000,000
Fixed-to-Floating Interest Rate Swaps \| Fair Value Hedging \| Designated as Hedging Instrument
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Interest rate fair value hedge liability at fair value	123,000,000	107,000,000
Forward Starting Interest Rate Swap \| Cash Flow Hedging \| Designated as Hedging Instrument
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Cash flow hedge derivative instrument assets at fair value	0	$ 48,000,000
Cash flow hedge derivative instrument liabilities at fair value	$ 0

Fair value of all asset derivatives designated as cash flow hedging instruments.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4B
-Subparagraph (c)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4B

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- Definition

Fair value of all liability derivatives designated as cash flow hedging instruments.

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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

No definition available.

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6A
-Subparagraph (e)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-6A

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- Definition

Fair value as of the balance sheet date of all derivative assets designated as interest rate fair value hedging instruments.

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