Income Taxes - Schedule of Effective Income Tax Reconciliation (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020
Income Tax Disclosure [Abstract]
Federal income tax rate	21.00%	21.00%	21.00%
Tax computed at statutory rate	$ 243	$ 270	$ 196
Increase (decrease) resulting from:
State income taxes, net of federal income tax benefit	31	32	9
Bank-owned life insurance	(4)	(7)	(6)
401(k) – employee stock ownership plan	(1)	(1)	(1)
Tax-exempt interest	(10)	(10)	(8)
Non-deductible expenses	11	8	13
LIHTC credits and benefits, net of amortization	(16)	(14)	(9)
Other tax credits	(4)	(4)	(5)
Other changes in unrecognized tax benefits	(2)	4	(9)
Purchase accounting gain	0	0	(112)
Other	(1)	(4)	8
Total	$ 247	$ 274	$ 76