Securities (Schedule of Contractual Maturities of Securities) (Details) - USD ($) $ in Thousands	Jun. 30, 2020	Dec. 31, 2019
Available for Sale, Fair Value
Debt Securities, Available-for-sale, Amortized Cost	$ 400,341	$ 420,703
Debt Securities, Available-for-sale	420,517	426,424
Held to Maturity, Fair Value
Debt Securities, Held-to-maturity	731,026	740,806
Held to Maturity, Fair Value, Total	764,054	753,263
Available for Sale Securities and Held to Maturity Securities Amortized Cost	1,131,367
Debt Securities, Available-for-sale and Held-to-maturity	1,184,571
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Amortized Cost	9,816
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, within One Year, Fair Value	9,911
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Amortized Cost	87,124
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after One Through Five Years, Fair Value	90,398
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Amortized Cost	102,643
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Five Through Ten Years, Fair Value	109,619
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Amortized Cost	931,784
Debt Securities, Available-for-sale and Held-to-maturity, Maturity, Allocated and Single Maturity Date, after Ten Years, Fair Value	974,643
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	0
Available for Sale, Amortized Cost, Due after one year to five years	10,002
Available for Sale, Amortized Cost, Due after five to ten years	12,473
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	0
Available for Sale, Fair Value, Due after one year to five years	10,333
Available for Sale, Fair Value, Due after five to ten years	14,012
Available for Sale, Fair Value, Due after ten years	0
Debt Securities, Available-for-sale, Amortized Cost	22,475	32,473
Debt Securities, Available-for-sale	24,345	33,115
Held to Maturity, Fair Value
Debt Securities, Held-to-maturity	0	12,874
Held to Maturity, Fair Value, Total	0	12,997
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	60,558
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	63,977
Debt Securities, Available-for-sale, Amortized Cost	60,558	54,024
Debt Securities, Available-for-sale	63,977	54,795
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	28,925
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	30,366
Debt Securities, Held-to-maturity	28,925	31,324
Held to Maturity, Fair Value, Total	30,366	31,607
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	250
Available for Sale, Amortized Cost, Due after one year to five years	82,422
Available for Sale, Amortized Cost, Due after five to ten years	53,253
Available for Sale, Amortized Cost, Due after ten years	264,416
Available for Sale, Fair Value
Available for Sale, Fair Value, Due in one year or less	250
Available for Sale, Fair Value, Due after one year to five years	85,576
Available for Sale, Fair Value, Due after five to ten years	57,781
Available for Sale, Fair Value, Due after ten years	276,910
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	9,566
Held to Maturity, Amortized Cost, Due after one year to five years	4,702
Held to Maturity, Amortized Cost, Due after five to ten years	49,390
Held to Maturity, Amortized Cost, Due after ten years	667,368
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	9,661
Held to Maturity, Fair Value, Due after one year to five years	4,822
Held to Maturity, Fair Value, Due after five to ten years	51,838
Held to Maturity, Fair Value, Due after ten years	697,733
Held to Maturity, Fair Value, Total	764,054
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	1,438
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	986
Debt Securities, Available-for-sale, Amortized Cost	1,438	1,488
Debt Securities, Available-for-sale	986	1,114
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	445
Debt Securities, Available-for-sale, Amortized Cost	489	488
Debt Securities, Available-for-sale	445	493
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	1,498
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	1,498	1,490
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	250
Available for Sale, Amortized Cost, Due after one year to five years	686
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	250
Available for Sale, Fair Value, Due after one year to five years	690
Available for Sale, Fair Value, Due after five to ten years	207
Available for Sale, Fair Value, Due after ten years	0
Debt Securities, Available-for-sale, Amortized Cost	1,126	1,377
Debt Securities, Available-for-sale	1,147	1,396
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	77,036
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	80,812
Debt Securities, Available-for-sale, Amortized Cost	77,036	87,305
Debt Securities, Available-for-sale	80,812	88,511
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	264,675
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	275,035
Debt Securities, Held-to-maturity	264,675	293,662
Held to Maturity, Fair Value, Total	275,035	297,314
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	71,734
Available for Sale, Amortized Cost, Due after five to ten years	40,590
Available for Sale, Amortized Cost, Due after ten years	124,895
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	74,553
Available for Sale, Fair Value, Due after five to ten years	43,562
Available for Sale, Fair Value, Due after ten years	130,690
Debt Securities, Available-for-sale, Amortized Cost	237,219	243,548
Debt Securities, Available-for-sale	248,805	247,000
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	8,565
Held to Maturity, Amortized Cost, Due after one year to five years	1,678
Held to Maturity, Amortized Cost, Due after five to ten years	47,890
Held to Maturity, Amortized Cost, Due after ten years	373,768
Held to Maturity, Fair Value
Held to Maturity, Fair Value, Due in one year or less	8,635
Held to Maturity, Fair Value, Due after one year to five years	1,729
Held to Maturity, Fair Value, Due after five to ten years	50,340
Held to Maturity, Fair Value, Due after ten years	392,332
Debt Securities, Held-to-maturity	431,901	397,414
Held to Maturity, Fair Value, Total	453,036	405,802
US Treasury Securities [Member]
Held to Maturity, Amortized Cost
Held to Maturity, Amortized Cost, Due in one year or less	1,001
Held to Maturity, Amortized Cost, Due after one year to five years	3,024
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	1,026
Held to Maturity, Fair Value, Due after one year to five years	3,093
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	4,025	4,032
Held to Maturity, Fair Value, Total	$ 4,119	$ 4,053