Investment Securities (Scheduled Maturities of Securities Available for Sale and Securities Held to Maturity) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Investments [Abstract]
Debt securities available for sale, Due in one year or less, Amortized Cost	$ 6,192
Debt securities available for sale, Due from one to five years, Amortized Cost	92,170
Debt securities available for sale, Due after five years through ten years, Amortized Cost	160,564
Debt securities available for sale, Due after ten years, Amortized Cost	941,773
Securities available for sale, Amortized Cost	1,200,699	$ 1,184,835
Debt securities available for sale, Due in one year or less, Fair Value	6,213
Debt securities available for sale, Due from one to five years, Fair Value	91,021
Debt securities available for sale, Due after five years through ten years, Fair Value	153,197
Debt securities available for sale, Due after ten years, Fair Value	868,931
Debt securities available for sale, Fair Value	1,119,362	1,178,515
Debt securities held to maturity, Due in one year or less, Amortized Cost	34,381
Debt securities held to maturity, Due from one to five years, Amortized Cost	64,649
Debt securities held to maturity, Due after five years through ten years, Amortized Cost	21,192
Debt securities held to maturity, Due after ten years, Amortized Cost	90,957
Securities held to maturity, Amortized Cost	211,179	205,586
Debt securities held to maturity, Due in one year or less, Fair Value	34,462
Debt securities held to maturity, Due from one to five years, Fair Value	64,564
Debt securities held to maturity, Due after five years through ten years, Fair Value	20,350
Debt securities held to maturity, Due after ten years, Fair Value	86,991
Securities held to maturity, Fair Value	$ 206,367	$ 209,820