Investment Securities Held to Maturity (Details) $ in Thousands	Jun. 30, 2019 USD ($) security	Dec. 31, 2018 USD ($) security	Jun. 30, 2018 USD ($) security
Schedule of Held-to-maturity Securities [Line Items]
Held-To-Maturity Securities, at Amortized Cost	$ 262,541	$ 283,476	$ 297,885
Held-To-Maturity Securities, at Fair Value	266,068	280,338	292,605
Gross Unrealized Gains	3,621	486	497
Gross Unrealized Losses	94	3,624	5,777
Maturities of Debt Securities, at Amortized Cost:
Within One Year	25,944
From 1 - 5 Years	154,910
From 5 - 10 Years	80,037
Over 10 Years	1,650
Maturities of Debt Securities, at Fair Value:
Within One Year	26,016
From 1 - 5 Years	156,780
From 5 - 10 Years	81,593
Over 10 Years	1,679
Securities in a Continuous Loss Position, at Fair Value:
Less than 12 Months	92	65,402	118,589
12 Months or Longer	16,085	124,617	93,735
Total	$ 16,177	$ 190,019	$ 212,324
Number of Securities in a Continuous Loss Position | security	37	458	512
Unrealized Losses on Securities in a Continuous Loss Position:
Less than 12 Months	$ 0	$ 618	$ 1,654
12 Months or Longer	94	3,006	4,123
Total	94	3,624	5,777
Equity Securities	1,850	1,774	1,802
State and Municipal Obligations
Schedule of Held-to-maturity Securities [Line Items]
Held-To-Maturity Securities, at Amortized Cost	220,529	235,782	244,016
Held-To-Maturity Securities, at Fair Value	223,654	233,359	239,841
Gross Unrealized Gains	3,206	486	497
Gross Unrealized Losses	81	2,909	4,672
Maturities of Debt Securities, at Amortized Cost:
Within One Year	24,060
From 1 - 5 Years	114,782
From 5 - 10 Years	80,037
Over 10 Years	1,650
Maturities of Debt Securities, at Fair Value:
Within One Year	24,109
From 1 - 5 Years	116,273
From 5 - 10 Years	81,593
Over 10 Years	1,679
Securities in a Continuous Loss Position, at Fair Value:
Less than 12 Months	159	32,093	68,612
12 Months or Longer	14,374	110,947	90,948
Total	$ 14,533	$ 143,040	$ 159,560
Number of Securities in a Continuous Loss Position | security	36	411	465
Unrealized Losses on Securities in a Continuous Loss Position:
Less than 12 Months	$ 0	$ 162	$ 633
12 Months or Longer	81	2,747	4,039
Total	81	2,909	4,672
Mortgage-Backed Securities - Residential
Schedule of Held-to-maturity Securities [Line Items]
Held-To-Maturity Securities, at Amortized Cost	42,012	47,694	53,869
Held-To-Maturity Securities, at Fair Value	42,414	46,979	52,764
Gross Unrealized Gains	415	0	0
Gross Unrealized Losses	13	715	1,105
Maturities of Debt Securities, at Amortized Cost:
Within One Year	1,884
From 1 - 5 Years	40,128
From 5 - 10 Years	0
Over 10 Years	0
Maturities of Debt Securities, at Fair Value:
Within One Year	1,907
From 1 - 5 Years	40,507
From 5 - 10 Years	0
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value:
Less than 12 Months	(67)	33,309	49,977
12 Months or Longer	1,711	13,670	2,787
Total	$ 1,644	$ 46,979	$ 52,764
Number of Securities in a Continuous Loss Position | security	1	47	47
Unrealized Losses on Securities in a Continuous Loss Position:
Less than 12 Months	$ 0	$ 456	$ 1,021
12 Months or Longer	13	259	84
Total	13	715	1,105
Fair Value, Measurements, Recurring
Unrealized Losses on Securities in a Continuous Loss Position:
Equity Securities	1,850	1,774	1,802
Collateral Pledged
Schedule of Held-to-maturity Securities [Line Items]
Held-To-Maturity Securities, Pledged as Collateral	251,639	266,341	278,627
US Government Agencies Debt Securities | Mortgage-Backed Securities - Residential
Schedule of Held-to-maturity Securities [Line Items]
Held-To-Maturity Securities, at Amortized Cost	1,942	2,180	3,265
US Government Agencies Debt Securities | Fair Value, Measurements, Recurring | Mortgage-Backed Securities - Residential
Schedule of Held-to-maturity Securities [Line Items]
Held-To-Maturity Securities, at Fair Value	1,948	2,143	2,346
US Government-sponsored Enterprises Debt Securities | Mortgage-Backed Securities - Residential
Schedule of Held-to-maturity Securities [Line Items]
Held-To-Maturity Securities, at Amortized Cost	40,070	45,514	50,604
US Government-sponsored Enterprises Debt Securities | Fair Value, Measurements, Recurring | Mortgage-Backed Securities - Residential
Schedule of Held-to-maturity Securities [Line Items]
Held-To-Maturity Securities, at Fair Value	$ 40,466	$ 44,836	$ 50,418