Securities (Schedule of Contractual Maturities of Securities) (Details) - USD ($) $ in Thousands	Mar. 31, 2021	Dec. 31, 2020
Available for Sale, Fair Value
Debt Securities, Available-for-sale, Amortized Cost	$ 593,167	$ 395,453
Debt Securities, Available-for-sale	600,213	412,860
Held to Maturity, Fair Value
Debt Securities, Held-to-maturity	805,529	724,512
Held to Maturity, Fair Value, Total	820,430	752,177
Available for Sale Securities and Held to Maturity Securities Amortized Cost	1,398,696
Debt Securities, Available-for-sale and Held-to-maturity	1,420,643
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	14,365
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	14,588
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	84,783
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	87,678
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	388,485
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	384,403
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Amortized Cost	911,063
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Fair Value	933,974
U.S. government agency securities
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for Sale, Amortized Cost, Due in one year or less	10,001
Available for Sale, Amortized Cost, Due after one year to five years	0
Available for Sale, Amortized Cost, Due after five to ten years	159,090
Available for Sale, Amortized Cost, Due after ten years	0
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	10,180
Available for Sale, Fair Value, Due after one year to five years	0
Available for Sale, Fair Value, Due after five to ten years	157,876
Available for Sale, Fair Value, Due after ten years	0
Debt Securities, Available-for-sale, Amortized Cost	169,091	22,476
Debt Securities, Available-for-sale	168,056	24,116
Small Business Administration Pooled Securities [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for Sale, Amortized Cost, Due in one year or less	0
Available for Sale, Amortized Cost, Due after one year to five years	0
Available for Sale, Amortized Cost, Due after five to ten years	0
Available for Sale, Amortized Cost, Due after ten years	56,171
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	0
Available for Sale, Fair Value, Due after one year to five years	0
Available for Sale, Fair Value, Due after five to ten years	0
Available for Sale, Fair Value, Due after ten years	58,246
Debt Securities, Available-for-sale, Amortized Cost	56,171	57,289
Debt Securities, Available-for-sale	58,246	61,081
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	0
Held to Maturity, Amortized Cost, Due after one year to five years	0
Held to Maturity, Amortized Cost, Due after five to ten years	0
Held to Maturity, Amortized Cost, Due after ten years	26,518
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	0
Held to Maturity, Fair Value, Due after one year to five years	0
Held to Maturity, Fair Value, Due after five to ten years	0
Held to Maturity, Fair Value, Due after ten years	27,235
Debt Securities, Held-to-maturity	26,518	26,917
Held to Maturity, Fair Value, Total	27,235	28,362
Debt Securities [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for Sale, Amortized Cost, Due in one year or less	10,351
Available for Sale, Amortized Cost, Due after one year to five years	80,169
Available for Sale, Amortized Cost, Due after five to ten years	258,027
Available for Sale, Amortized Cost, Due after ten years	244,620
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	10,531
Available for Sale, Fair Value, Due after one year to five years	82,809
Available for Sale, Fair Value, Due after five to ten years	254,994
Available for Sale, Fair Value, Due after ten years	251,879
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	4,014
Held to Maturity, Amortized Cost, Due after one year to five years	4,614
Held to Maturity, Amortized Cost, Due after five to ten years	130,458
Held to Maturity, Amortized Cost, Due after ten years	666,443
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	4,057
Held to Maturity, Fair Value, Due after one year to five years	4,869
Held to Maturity, Fair Value, Due after five to ten years	129,409
Held to Maturity, Fair Value, Due after ten years	682,095
Held to Maturity, Fair Value, Total	820,430
Pooled trust preferred securities issued by banks and insurers
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for Sale, Amortized Cost, Due in one year or less	0
Available for Sale, Amortized Cost, Due after one year to five years	0
Available for Sale, Amortized Cost, Due after five to ten years	0
Available for Sale, Amortized Cost, Due after ten years	1,412
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	0
Available for Sale, Fair Value, Due after one year to five years	0
Available for Sale, Fair Value, Due after five to ten years	0
Available for Sale, Fair Value, Due after ten years	1,064
Debt Securities, Available-for-sale, Amortized Cost	1,412	1,429
Debt Securities, Available-for-sale	1,064	1,056
Single Issuer Trust Preferred Securities Issued by Banks and Insurers [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for Sale, Amortized Cost, Due in one year or less	0
Available for Sale, Amortized Cost, Due after one year to five years	0
Available for Sale, Amortized Cost, Due after five to ten years	0
Available for Sale, Amortized Cost, Due after ten years	489
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	0
Available for Sale, Fair Value, Due after one year to five years	0
Available for Sale, Fair Value, Due after five to ten years	0
Available for Sale, Fair Value, Due after ten years	488
Debt Securities, Available-for-sale, Amortized Cost	489	489
Debt Securities, Available-for-sale	488	488
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	0
Held to Maturity, Amortized Cost, Due after one year to five years	0
Held to Maturity, Amortized Cost, Due after five to ten years	1,500
Held to Maturity, Amortized Cost, Due after ten years	0
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	0
Held to Maturity, Fair Value, Due after one year to five years	0
Held to Maturity, Fair Value, Due after five to ten years	1,508
Held to Maturity, Fair Value, Due after ten years	0
Debt Securities, Held-to-maturity	1,500	1,500
Held to Maturity, Fair Value, Total	1,508	1,498
US States and Political Subdivisions Debt Securities [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for Sale, Amortized Cost, Due in one year or less	350
Available for Sale, Amortized Cost, Due after one year to five years	0
Available for Sale, Amortized Cost, Due after five to ten years	190
Available for Sale, Amortized Cost, Due after ten years	0
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	351
Available for Sale, Fair Value, Due after one year to five years	0
Available for Sale, Fair Value, Due after five to ten years	204
Available for Sale, Fair Value, Due after ten years	0
Debt Securities, Available-for-sale, Amortized Cost	540	790
Debt Securities, Available-for-sale	555	807
Agency Collateralized Mortgage Obligations [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for Sale, Amortized Cost, Due in one year or less	0
Available for Sale, Amortized Cost, Due after one year to five years	0
Available for Sale, Amortized Cost, Due after five to ten years	0
Available for Sale, Amortized Cost, Due after ten years	78,952
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	0
Available for Sale, Fair Value, Due after one year to five years	0
Available for Sale, Fair Value, Due after five to ten years	0
Available for Sale, Fair Value, Due after ten years	81,629
Debt Securities, Available-for-sale, Amortized Cost	78,952	88,687
Debt Securities, Available-for-sale	81,629	91,683
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	0
Held to Maturity, Amortized Cost, Due after one year to five years	0
Held to Maturity, Amortized Cost, Due after five to ten years	0
Held to Maturity, Amortized Cost, Due after ten years	355,686
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	0
Held to Maturity, Fair Value, Due after one year to five years	0
Held to Maturity, Fair Value, Due after five to ten years	0
Held to Maturity, Fair Value, Due after ten years	361,002
Debt Securities, Held-to-maturity	355,686	335,993
Held to Maturity, Fair Value, Total	361,002	344,119
Mortgage-backed Securities, Issued by US Government Sponsored Enterprises [Member]
Schedule of Available-for-sale Securities and Held-to-maturity Securities [Line Items]
Available for Sale, Amortized Cost, Due in one year or less	0
Available for Sale, Amortized Cost, Due after one year to five years	80,169
Available for Sale, Amortized Cost, Due after five to ten years	98,747
Available for Sale, Amortized Cost, Due after ten years	107,596
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	0
Available for Sale, Fair Value, Due after one year to five years	82,809
Available for Sale, Fair Value, Due after five to ten years	96,914
Available for Sale, Fair Value, Due after ten years	110,452
Debt Securities, Available-for-sale, Amortized Cost	286,512	224,293
Debt Securities, Available-for-sale	290,175	233,629
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	0
Held to Maturity, Amortized Cost, Due after one year to five years	4,614
Held to Maturity, Amortized Cost, Due after five to ten years	128,958
Held to Maturity, Amortized Cost, Due after ten years	284,239
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	0
Held to Maturity, Fair Value, Due after one year to five years	4,869
Held to Maturity, Fair Value, Due after five to ten years	127,901
Held to Maturity, Fair Value, Due after ten years	293,858
Debt Securities, Held-to-maturity	417,811	356,085
Held to Maturity, Fair Value, Total	426,628	374,121
US Treasury Securities [Member]
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	4,014
Held to Maturity, Amortized Cost, Due after one year to five years	0
Held to Maturity, Amortized Cost, Due after five to ten years	0
Held to Maturity, Amortized Cost, Due after ten years	0
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	4,057
Held to Maturity, Fair Value, Due after one year to five years	0
Held to Maturity, Fair Value, Due after five to ten years	0
Held to Maturity, Fair Value, Due after ten years	0
Debt Securities, Held-to-maturity	4,014	4,017
Held to Maturity, Fair Value, Total	$ 4,057	$ 4,077