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Business Combinations (Details) - USD ($) $ in Millions		3 Months Ended
	Feb. 19, 2024	Mar. 31, 2025
Business Acquisition [Line Items]
Entity shares issued (in shares)	1.0192
Business combination, acquisition related costs		$ 110
Business combination, acquisition related cost, recognized		$ 344
Series D Preferred Stock | Discover
Business Acquisition [Line Items]
Per annum dividend rate	6.125%

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