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Loans and Allowance for Credit Losses - Narrative (Details) $ in Millions	3 Months Ended	12 Months Ended
	Dec. 31, 2025 USD ($) loan	Dec. 31, 2025 USD ($) loan loanSegment	Dec. 31, 2024 USD ($) loan	Dec. 31, 2023 USD ($)
Financing Receivable, Credit Quality Indicator [Line Items]
Number of loan segments \| loanSegment		2
Loans	$ 46,589	$ 46,589	$ 43,026
Number of loans on non-accrual status \| loan	4	4	2
Non-accrual loans	$ 258	$ 258	$ 191
Sale of loans		1,068	246	$ 506
Provision for credit losses	59	59	75	46
Allowance for credit losses	$ 193	$ 193	174
Investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Percent or loans	91.00%	91.00%
Sub-investment grade
Financing Receivable, Credit Quality Indicator [Line Items]
Percent or loans	8.00%	8.00%
Sub-investment grade \| External credit rating, or equivalent, of “BB” or “B”
Financing Receivable, Credit Quality Indicator [Line Items]
Percent or loans	87.00%	87.00%
Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Loans no longer meeting similar risk of collective pool \| loan	3	3
Loans no longer meeting similar risk of collective pool	$ 98	$ 98
Commercial Real Estate
Financing Receivable, Credit Quality Indicator [Line Items]
Loans no longer meeting similar risk of collective pool \| loan	4	4
Loans no longer meeting similar risk of collective pool	$ 296	$ 296
Loans No Longer Meeting Similar Risk of Collective Pool
Financing Receivable, Credit Quality Indicator [Line Items]
Allowance for credit losses	120	120
Collateralized loan obligations
Financing Receivable, Credit Quality Indicator [Line Items]
Payments to acquire loans receivable		5,570
Broadly syndicated CLOs
Financing Receivable, Credit Quality Indicator [Line Items]
Payments to acquire loans receivable		5,010
Middle market CLOs
Financing Receivable, Credit Quality Indicator [Line Items]
Payments to acquire loans receivable		560
Commercial
Financing Receivable, Credit Quality Indicator [Line Items]
Sale of loans		1,160
Provision for credit losses		(15)
Commercial \| Commercial and Financial
Financing Receivable, Credit Quality Indicator [Line Items]
Provision for credit losses		16	13
Allowance for credit losses	$ 69	$ 69	$ 68	$ 72
Non-accrual status, more than 90 days
Financing Receivable, Credit Quality Indicator [Line Items]
Number of loans on non-accrual status \| loan	0	0	1
Non-accrual loans			$ 101
Pledged as collateral
Financing Receivable, Credit Quality Indicator [Line Items]
Loans	$ 15,110	$ 15,110	$ 13,900