Fair Value Measurements - Schedule of Assets at Fair Value Recurring Basis (Details) - USD ($) $ in Millions	Jun. 30, 2026	Dec. 31, 2025
Investment securities:
Available-for-sale securities	$ 1,587	$ 1,532
Other securities	62	58
U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	13	13
Obligations of states, municipalities, and political subdivisions
Investment securities:
Available-for-sale securities	54	56
Commercial paper
Investment securities:
Available-for-sale securities	58	0
Non-U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	137	157
Corporate debt
Investment securities:
Available-for-sale securities	1,048	1,030
RMBS
Investment securities:
Available-for-sale securities	190	190
CMBS
Investment securities:
Available-for-sale securities	18	22
CDO/ABS
Investment securities:
Available-for-sale securities	69	64
Level 1
Investment securities:
Total investment securities	62	57
Level 2
Investment securities:
Total investment securities	1,584	1,530
Level 3
Investment securities:
Total investment securities	3	3
Fair Value, Measurements, Recurring
Assets
Cash equivalents in mutual funds	57	48
Cash equivalents in securities	5	53
Investment securities:
Available-for-sale securities	1,587	1,532
Other securities	62	58
Total investment securities	1,649	1,590
Restricted cash equivalents in mutual funds	569	620
Total	2,280	2,311
Fair Value, Measurements, Recurring \| Total bonds
Investment securities:
Other securities	4	6
Fair Value, Measurements, Recurring \| U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	13	13
Fair Value, Measurements, Recurring \| Obligations of states, municipalities, and political subdivisions
Investment securities:
Available-for-sale securities	54	56
Fair Value, Measurements, Recurring \| Commercial paper
Investment securities:
Available-for-sale securities	58
Fair Value, Measurements, Recurring \| Non-U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	137	157
Fair Value, Measurements, Recurring \| Corporate debt
Investment securities:
Available-for-sale securities	1,048	1,030
Other securities	3	3
Fair Value, Measurements, Recurring \| RMBS
Investment securities:
Available-for-sale securities	190	190
Fair Value, Measurements, Recurring \| CMBS
Investment securities:
Available-for-sale securities	18	22
Fair Value, Measurements, Recurring \| CDO/ABS
Investment securities:
Available-for-sale securities	69	64
Other securities	1	3
Fair Value, Measurements, Recurring \| Preferred stock
Investment securities:
Other securities	12	12
Fair Value, Measurements, Recurring \| Common stock
Investment securities:
Other securities	46	40
Fair Value, Measurements, Recurring \| Level 1
Assets
Cash equivalents in mutual funds	57	48
Cash equivalents in securities	0	0
Investment securities:
Available-for-sale securities	5	6
Other securities	57	51
Total investment securities	62	57
Restricted cash equivalents in mutual funds	569	620
Total	688	725
Fair Value, Measurements, Recurring \| Level 1 \| Total bonds
Investment securities:
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Obligations of states, municipalities, and political subdivisions
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Commercial paper
Investment securities:
Available-for-sale securities	0
Fair Value, Measurements, Recurring \| Level 1 \| Non-U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Corporate debt
Investment securities:
Available-for-sale securities	5	6
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| RMBS
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| CMBS
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| CDO/ABS
Investment securities:
Available-for-sale securities	0	0
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 1 \| Preferred stock
Investment securities:
Other securities	12	12
Fair Value, Measurements, Recurring \| Level 1 \| Common stock
Investment securities:
Other securities	45	39
Fair Value, Measurements, Recurring \| Level 2
Assets
Cash equivalents in mutual funds	0	0
Cash equivalents in securities	5	53
Investment securities:
Available-for-sale securities	1,580	1,524
Other securities	4	6
Total investment securities	1,584	1,530
Restricted cash equivalents in mutual funds	0	0
Total	1,589	1,583
Fair Value, Measurements, Recurring \| Level 2 \| Total bonds
Investment securities:
Other securities	4	6
Fair Value, Measurements, Recurring \| Level 2 \| U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	13	13
Fair Value, Measurements, Recurring \| Level 2 \| Obligations of states, municipalities, and political subdivisions
Investment securities:
Available-for-sale securities	54	56
Fair Value, Measurements, Recurring \| Level 2 \| Commercial paper
Investment securities:
Available-for-sale securities	58
Fair Value, Measurements, Recurring \| Level 2 \| Non-U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	137	157
Fair Value, Measurements, Recurring \| Level 2 \| Corporate debt
Investment securities:
Available-for-sale securities	1,041	1,022
Other securities	3	3
Fair Value, Measurements, Recurring \| Level 2 \| RMBS
Investment securities:
Available-for-sale securities	190	190
Fair Value, Measurements, Recurring \| Level 2 \| CMBS
Investment securities:
Available-for-sale securities	18	22
Fair Value, Measurements, Recurring \| Level 2 \| CDO/ABS
Investment securities:
Available-for-sale securities	69	64
Other securities	1	3
Fair Value, Measurements, Recurring \| Level 2 \| Preferred stock
Investment securities:
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 2 \| Common stock
Investment securities:
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 3
Assets
Cash equivalents in mutual funds	0	0
Cash equivalents in securities	0	0
Investment securities:
Available-for-sale securities	2	2
Other securities	1	1
Total investment securities	3	3
Restricted cash equivalents in mutual funds	0	0
Total	3	3
Fair Value, Measurements, Recurring \| Level 3 \| Total bonds
Investment securities:
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Obligations of states, municipalities, and political subdivisions
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Commercial paper
Investment securities:
Available-for-sale securities	0
Fair Value, Measurements, Recurring \| Level 3 \| Non-U.S. government and government sponsored entities
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Corporate debt
Investment securities:
Available-for-sale securities	2	2
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| RMBS
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| CMBS
Investment securities:
Available-for-sale securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| CDO/ABS
Investment securities:
Available-for-sale securities	0	0
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Preferred stock
Investment securities:
Other securities	0	0
Fair Value, Measurements, Recurring \| Level 3 \| Common stock
Investment securities:
Other securities	$ 1	$ 1

Cash and Cash Equivalents in Investment Securities, Fair Value Disclosure

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Represents the fair value of cash and cash equivalents in mutual funds.

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Fair value portion of asset recognized for present right to economic benefit.

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Amount excluding accrued interest, of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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