Investment Securities - Available for Sale (Details) $ in Thousands	Mar. 31, 2021 USD ($) security	Dec. 31, 2020 USD ($) security	Mar. 31, 2020 USD ($) security
Available-For-Sale Securities
Available-For-Sale Securities, at Amortized Cost	$ 461,420	$ 357,497	$ 372,058
Gross Unrealized Gains	6,414	8,118	7,663
Gross Unrealized Losses	(3,745)	(328)	(1,535)
Available-for-Sale at Fair Value	464,089	365,287	378,186
Maturities of Debt Securities, at Amortized Cost:
Within One Year	126
From 1 - 5 Years	354,782
From 5 - 10 Years	106,512
Over 10 Years	0
Maturities of Debt Securities, at Fair Value:
Within One Year	132
From 1 - 5 Years	359,184
From 5 - 10 Years	104,773
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value:
Less than 12 Months	224,011	29,926	18,846
12 Months or Longer	800	5,682	60,062
Total	$ 224,811	$ 35,608	$ 78,908
Number of Securities in a Continuous Loss Position | security	31	6	28
Unrealized Losses on Securities in a Continuous Loss Position:
Less than 12 Months	$ 3,545	$ 74	$ 316
12 Months or Longer	200	254	1,219
Total	3,745	328	1,535
Collateral Pledged
Available-For-Sale Securities
Available-For-Sale Securities, Pledged as Collateral, at Fair Value	352,214	244,411	273,124
U.S. Government & Agency Obligations
Available-For-Sale Securities
Available-For-Sale Securities, at Amortized Cost	110,001	65,002	5,002
Gross Unrealized Gains	138	184	179
Gross Unrealized Losses	(1,769)	(74)	0
Available-for-Sale at Fair Value	108,370	65,112	5,181
Maturities of Debt Securities, at Amortized Cost:
Within One Year	0
From 1 - 5 Years	65,001
From 5 - 10 Years	45,000
Over 10 Years	0
Maturities of Debt Securities, at Fair Value:
Within One Year	0
From 1 - 5 Years	63,774
From 5 - 10 Years	44,596
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value:
Less than 12 Months	103,231	29,926	0
12 Months or Longer	0	0	0
Total	$ 103,231	$ 29,926	$ 0
Number of Securities in a Continuous Loss Position | security	14	4	0
Unrealized Losses on Securities in a Continuous Loss Position:
Less than 12 Months	$ 1,769	$ 74	$ 0
12 Months or Longer	0	0	0
Total	1,769	74	0
U.S. Government & Agency Obligations | Agency Securities
Available-For-Sale Securities
Available-For-Sale Securities, at Amortized Cost	110,001	65,002	5,002
Available-for-Sale at Fair Value	108,370	65,112	5,181
State and Municipal Obligations
Available-For-Sale Securities
Available-For-Sale Securities, at Amortized Cost	508	528	723
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	0	0	0
Available-for-Sale at Fair Value	508	528	723
Maturities of Debt Securities, at Amortized Cost:
Within One Year	68
From 1 - 5 Years	40
From 5 - 10 Years	400
Over 10 Years	0
Maturities of Debt Securities, at Fair Value:
Within One Year	68
From 1 - 5 Years	40
From 5 - 10 Years	400
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value:
Less than 12 Months	0	0	0
12 Months or Longer	0	0	0
Total	$ 0	$ 0	$ 0
Number of Securities in a Continuous Loss Position | security	0	0	0
Unrealized Losses on Securities in a Continuous Loss Position:
Less than 12 Months	$ 0	$ 0	$ 0
12 Months or Longer	0	0	0
Total	0	0	0
Mortgage- Backed Securities
Available-For-Sale Securities
Available-For-Sale Securities, at Amortized Cost	349,911	290,967	365,333
Gross Unrealized Gains	6,276	7,934	7,484
Gross Unrealized Losses	(1,776)	(54)	(1,335)
Available-for-Sale at Fair Value	354,411	298,847	371,482
Maturities of Debt Securities, at Amortized Cost:
Within One Year	58
From 1 - 5 Years	289,741
From 5 - 10 Years	60,112
Over 10 Years	0
Maturities of Debt Securities, at Fair Value:
Within One Year	64
From 1 - 5 Years	295,370
From 5 - 10 Years	58,977
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value:
Less than 12 Months	120,780	0	18,846
12 Months or Longer	0	4,882	59,262
Total	$ 120,780	$ 4,882	$ 78,108
Number of Securities in a Continuous Loss Position | security	16	1	27
Unrealized Losses on Securities in a Continuous Loss Position:
Less than 12 Months	$ 1,776	$ 0	$ 316
12 Months or Longer	0	54	1,019
Total	1,776	54	1,335
Mortgage- Backed Securities | US Government Agencies Debt Securities
Available-For-Sale Securities
Available-For-Sale Securities, at Amortized Cost	11,582	12,696	58,089
Available-for-Sale at Fair Value	11,658	12,683	57,091
Mortgage- Backed Securities | US Government-sponsored Enterprises Debt Securities
Available-For-Sale Securities
Available-For-Sale Securities, at Amortized Cost	338,329	278,271	307,244
Available-for-Sale at Fair Value	342,753	286,164	314,391
Corporate and Other Debt Securities
Available-For-Sale Securities
Available-For-Sale Securities, at Amortized Cost	1,000	1,000	1,000
Gross Unrealized Gains	0	0	0
Gross Unrealized Losses	(200)	(200)	(200)
Available-for-Sale at Fair Value	800	800	800
Maturities of Debt Securities, at Amortized Cost:
Within One Year	0
From 1 - 5 Years	0
From 5 - 10 Years	1,000
Over 10 Years	0
Maturities of Debt Securities, at Fair Value:
Within One Year	0
From 1 - 5 Years	0
From 5 - 10 Years	800
Over 10 Years	0
Securities in a Continuous Loss Position, at Fair Value:
Less than 12 Months	0	0	0
12 Months or Longer	800	800	800
Total	$ 800	$ 800	$ 800
Number of Securities in a Continuous Loss Position | security	1	1	1
Unrealized Losses on Securities in a Continuous Loss Position:
Less than 12 Months	$ 0	$ 0	$ 0
12 Months or Longer	200	200	200
Total	$ 200	$ 200	$ 200