Consolidated Statements of Condition (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2021	Dec. 31, 2020
Statement Of Financial Position [Abstract]
Held-to-Maturity: Fair Value	$ 4,895,763	$ 3,348,693
Preferred Stock, par value (in dollars per share)	$ 0.01
Preferred Stock, authorized (in shares)	180,000
Preferred Stock, issued (in shares)	180,000
Preferred Stock, outstanding (in shares)	180,000
Common Stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common Stock, authorized (in shares)	500,000,000	500,000,000
Common Stock, issued (in shares)	58,559,089	40,305,801
Common Stock, outstanding (in shares)	58,285,624	40,119,312
Treasury Stock (in shares)	18,253,288	18,166,312