Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2023	Mar. 31, 2022
Statement of Comprehensive Income [Abstract]
Net income for the period	$ 204	$ 203
Other comprehensive income (loss), net of tax:
Net unrealized holding gains (losses) on investment securities	126	(1,121)
Net unrealized holding gains (losses) on derivative instruments	29	(135)
Reclassification adjustment for decrease (increase) in interest income recognized in earnings on derivative instruments	37	(10)
Total other comprehensive income (loss), net of tax	192	(1,266)
Comprehensive income (loss)	$ 396	$ (1,063)