Equity Securities and Indexed Debt Securities (ZENS) - Narrative (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2026	Feb. 27, 2026	Sep. 30, 1999
Subordinated Debt, ZENS, Due 2029
Debt and Equity Securities, FV-NI [Line Items]
Aggregate principal			$ 1,000
Outstanding debt balance	$ 828
Subordinated note cash exchangeable percentage of fair value (as a percent)	95.00%
ZENS annual interest rate (as a percent)	2.00%
Target annual yield on reference shares (as a percent)	2.309%
Paramount Skydance Corporation (“Paramount”) and WBD Merger
Debt and Equity Securities, FV-NI [Line Items]
Consideration cash price for outstanding shares (in dollars per share)		$ 31.00