Securities - Debt Securities Available-for-Sale in Unrealized Loss Position (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Schedule Of Available For Sale Securities [Line Items]
Securities in unrealized loss position, Less Than 12 Months, Fair Value	$ 472,660	$ 479,322
Securities in unrealized loss position, Less Than 12 Months, Unrealized Losses	32,492	8,503
Securities in unrealized loss position, 12 Months or More, Fair Value	184,260	110,729
Securities in unrealized loss position, 12 Months or More, Unrealized Losses	18,678	3,709
Securities in unrealized loss position, Total, Fair Value	656,920	590,051
Securities in unrealized loss position, Total, Unrealized Losses	51,170	12,212
Mortgage-backed securities
Schedule Of Available For Sale Securities [Line Items]
Securities in unrealized loss position, Less Than 12 Months, Fair Value	472,660	479,322
Securities in unrealized loss position, Less Than 12 Months, Unrealized Losses	32,492	8,503
Securities in unrealized loss position, 12 Months or More, Fair Value	184,166	110,633
Securities in unrealized loss position, 12 Months or More, Unrealized Losses	18,673	3,706
Securities in unrealized loss position, Total, Fair Value	656,826	589,955
Securities in unrealized loss position, Total, Unrealized Losses	51,165	12,209
Municipal bonds
Schedule Of Available For Sale Securities [Line Items]
Securities in unrealized loss position, 12 Months or More, Fair Value	94	96
Securities in unrealized loss position, 12 Months or More, Unrealized Losses	5	3
Securities in unrealized loss position, Total, Fair Value	94	96
Securities in unrealized loss position, Total, Unrealized Losses	$ 5	$ 3