Investment Securities - Schedule of Amortized Cost and Fair Value of Debt Securities, Aggregated By Earlier of Guaranteed Call Date or Contractual Maturity (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Within One Year, Amortized Cost	$ 10,000
Available for sale securities, Within One Year, Fair Value	9,971
Available for sale securities, After One, But Within Five Years, Amortized Cost	40,058
Available for sale securities, After One, But Within Five Years, Fair Value	39,903
Available for sale securities, After Five, But Within Ten Years, Amortized Cost	29,462
Available for sale securities, After Five, But Within Ten Years, Fair Value	29,176
Available for sale securities, After Ten Years, Amortized Cost	74,245
Available for sale securities, After Ten Years, Fair Value	74,003
Available for sale securities, Total, Amortized Cost	153,765
Available for sale securities, Total, Fair Value	153,053
Held to maturity securities, Within One Year, Amortized Cost	7,429
Held to maturity securities, Within One Year, Fair Value	7,435
Held to maturity securities, After One, But Within Five Years, Amortized Cost	37,298
Held to maturity securities, After One, But Within Five Years, Fair Value	37,615
Held to maturity securities, After Five, But Within Ten Years, Amortized Cost	96,019
Held to maturity securities, After Five, But Within Ten Years, Fair Value	99,253
Held to maturity securities, After Ten Years, Amortized Cost	145,604
Held to maturity securities, After Ten Years, Fair Value	147,690
Held to maturity securities, Amortized Cost	286,350	$ 282,869
Held to maturity securities, Fair Value	291,993	281,310
Available for sale securities and Held to maturity securities, Within One Year, Amortized Cost	17,429
Available for sale securities and Held to maturity securities, Within One Year, Fair Value	17,406
Available for sale securities and Held to maturity securities, After One, But Within Five Years, Amortized Cost	77,356
Available for sale securities and Held to maturity securities, After One, But Within Five Years, Fair Value	77,518
Available for sale securities and Held to maturity securities, After Five, But Within Ten Years, Amortized Cost	125,481
Available for sale securities and Held to maturity securities, After Five, But Within Ten Years, Fair Value	128,429
Available for sale securities and Held to maturity securities, After Ten Years, Amortized Cost	219,849
Available for sale securities and Held to maturity securities, After Ten Years, Fair Value	221,693
Available for sale securities and Held to maturity securities, Total, Amortized Cost	440,115
Available for sale securities and Held to maturity securities, Total, Fair Value	445,046
U.S. GSE Obligations
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, Within One Year, Amortized Cost	10,000
Available for sale securities, Within One Year, Fair Value	9,971
Available for sale securities, After One, But Within Five Years, Amortized Cost	40,000
Available for sale securities, After One, But Within Five Years, Fair Value	39,844
Available for sale securities, Total, Amortized Cost	50,000
Available for sale securities, Total, Fair Value	49,815
Held to maturity securities, Within One Year, Amortized Cost	4,997
Held to maturity securities, Within One Year, Fair Value	4,982
Held to maturity securities, After One, But Within Five Years, Amortized Cost	17,575
Held to maturity securities, After One, But Within Five Years, Fair Value	17,576
Held to maturity securities, Amortized Cost	22,572
Held to maturity securities, Fair Value	22,558
Mortgage Backed Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Available for sale securities, After One, But Within Five Years, Amortized Cost	58
Available for sale securities, After One, But Within Five Years, Fair Value	59
Available for sale securities, After Five, But Within Ten Years, Amortized Cost	29,462
Available for sale securities, After Five, But Within Ten Years, Fair Value	29,176
Available for sale securities, After Ten Years, Amortized Cost	74,245
Available for sale securities, After Ten Years, Fair Value	74,003
Available for sale securities, Total, Amortized Cost	103,765
Available for sale securities, Total, Fair Value	103,238
Held to maturity securities, Within One Year, Amortized Cost	8
Held to maturity securities, Within One Year, Fair Value	8
Held to maturity securities, After Five, But Within Ten Years, Amortized Cost	52,063
Held to maturity securities, After Five, But Within Ten Years, Fair Value	53,202
Held to maturity securities, After Ten Years, Amortized Cost	129,705
Held to maturity securities, After Ten Years, Fair Value	131,218
Held to maturity securities, Amortized Cost	181,776
Held to maturity securities, Fair Value	184,428
Corporate Debt Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Held to maturity securities, After One, But Within Five Years, Amortized Cost	6,977
Held to maturity securities, After One, But Within Five Years, Fair Value	7,069
Held to maturity securities, Amortized Cost	6,977
Held to maturity securities, Fair Value	7,069
Municipal Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Held to maturity securities, Within One Year, Amortized Cost	2,424
Held to maturity securities, Within One Year, Fair Value	2,445
Held to maturity securities, After One, But Within Five Years, Amortized Cost	12,746
Held to maturity securities, After One, But Within Five Years, Fair Value	12,970
Held to maturity securities, After Five, But Within Ten Years, Amortized Cost	43,956
Held to maturity securities, After Five, But Within Ten Years, Fair Value	46,051
Held to maturity securities, After Ten Years, Amortized Cost	15,899
Held to maturity securities, After Ten Years, Fair Value	16,472
Held to maturity securities, Amortized Cost	75,025	75,208
Held to maturity securities, Fair Value	$ 77,938	$ 76,150

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