Investment Securities (Scheduled Maturities of Securities Available for Sale and Securities Held to Maturity) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Investments [Abstract]
Debt securities available for sale, Due in one year or less, Amortized Cost	$ 1,907
Debt securities available for sale, Due from one to five years, Amortized Cost	39,712
Debt securities available for sale, Due after five years through ten years, Amortized Cost	159,570
Debt securities available for sale, Due after ten years, Amortized Cost	406,476
Securities available for sale, Amortized Cost	607,665	$ 415,852
Debt securities available for sale, Due in one year or less, Fair Value	1,920
Debt securities available for sale, Due from one to five years, Fair Value	41,903
Debt securities available for sale, Due after five years through ten years, Fair Value	171,036
Debt securities available for sale, Due after ten years, Fair Value	413,200
Debt securities available for sale, Fair Value	628,059	417,917
Debt securities held to maturity, Due in one year or less, Amortized Cost	47,086
Debt securities held to maturity, Due from one to five years, Amortized Cost	97,363
Debt securities held to maturity, Due after five years through ten years, Amortized Cost	17,371
Debt securities held to maturity, Due after ten years, Amortized Cost	110,153
Securities held to maturity, Amortized Cost	271,973	359,000
Debt securities held to maturity, Due in one year or less, Fair Value	47,505
Debt securities held to maturity, Due from one to five years, Fair Value	101,311
Debt securities held to maturity, Due after five years through ten years, Fair Value	18,194
Debt securities held to maturity, Due after ten years, Fair Value	115,025
Securities held to maturity, Fair Value	$ 282,035	$ 363,259