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	Dec. 31, 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	$ 5,000
Available for sale securities, Within One Year, Fair Value	4,997
Available for sale securities, After One, But Within Five Years, Amortized Cost	20,037
Available for sale securities, After One, But Within Five Years, Fair Value	19,977
Available for sale securities, After Five, But Within Ten Years, Amortized Cost	41,393
Available for sale securities, After Five, But Within Ten Years, Fair Value	40,931
Available for sale securities, After Ten Years, Amortized Cost	74,679
Available for sale securities, After Ten Years, Fair Value	74,425
Available for sale securities, Total, Amortized Cost	141,109
Available for sale securities, Total, Fair Value	140,330
Held to maturity securities, Within One Year, Amortized Cost	8,270
Held to maturity securities, Within One Year, Fair Value	8,291
Held to maturity securities, After One, But Within Five Years, Amortized Cost	17,588
Held to maturity securities, After One, But Within Five Years, Fair Value	18,000
Held to maturity securities, After Five, But Within Ten Years, Amortized Cost	93,289
Held to maturity securities, After Five, But Within Ten Years, Fair Value	96,640
Held to maturity securities, After Ten Years, Amortized Cost	139,025
Held to maturity securities, After Ten Years, Fair Value	141,183
Held to maturity securities, Amortized Cost	258,172	$ 282,869
Held to maturity securities, Fair Value	264,114	281,310
Available for sale securities and Held to maturity securities, Within One Year, Amortized Cost	13,270
Available for sale securities and Held to maturity securities, Within One Year, Fair Value	13,288
Available for sale securities and Held to maturity securities, After One, But Within Five Years, Amortized Cost	37,625
Available for sale securities and Held to maturity securities, After One, But Within Five Years, Fair Value	37,977
Available for sale securities and Held to maturity securities, After Five, But Within Ten Years, Amortized Cost	134,682
Available for sale securities and Held to maturity securities, After Five, But Within Ten Years, Fair Value	137,571
Available for sale securities and Held to maturity securities, After Ten Years, Amortized Cost	213,704
Available for sale securities and Held to maturity securities, After Ten Years, Fair Value	215,608
Available for sale securities and Held to maturity securities, Total, Amortized Cost	399,281
Available for sale securities and Held to maturity securities, Total, Fair Value	404,444
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	5,000
Available for sale securities, Within One Year, Fair Value	4,997
Available for sale securities, After One, But Within Five Years, Amortized Cost	20,000
Available for sale securities, After One, But Within Five Years, Fair Value	19,939
Available for sale securities, After Five, But Within Ten Years, Amortized Cost	5,000
Available for sale securities, After Five, But Within Ten Years, Fair Value	4,934
Available for sale securities, After Ten Years, Amortized Cost	8,000
Available for sale securities, After Ten Years, Fair Value	7,978
Available for sale securities, Total, Amortized Cost	38,000
Available for sale securities, Total, Fair Value	37,848
Held to maturity securities, Within One Year, Amortized Cost	5,000
Held to maturity securities, Within One Year, Fair Value	5,000
Held to maturity securities, Amortized Cost	5,000
Held to maturity securities, Fair Value	5,000
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	37
Available for sale securities, After One, But Within Five Years, Fair Value	38
Available for sale securities, After Five, But Within Ten Years, Amortized Cost	36,393
Available for sale securities, After Five, But Within Ten Years, Fair Value	35,997
Available for sale securities, After Ten Years, Amortized Cost	66,679
Available for sale securities, After Ten Years, Fair Value	66,447
Available for sale securities, Total, Amortized Cost	103,109
Available for sale securities, Total, Fair Value	102,482
Held to maturity securities, After One, But Within Five Years, Amortized Cost	2
Held to maturity securities, After One, But Within Five Years, Fair Value	2
Held to maturity securities, After Five, But Within Ten Years, Amortized Cost	48,088
Held to maturity securities, After Five, But Within Ten Years, Fair Value	49,117
Held to maturity securities, After Ten Years, Amortized Cost	113,669
Held to maturity securities, After Ten Years, Fair Value	115,280
Held to maturity securities, Amortized Cost	161,759
Held to maturity securities, Fair Value	164,399
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	6,980
Held to maturity securities, After One, But Within Five Years, Fair Value	7,096
Held to maturity securities, Amortized Cost	6,980
Held to maturity securities, Fair Value	7,096
Municipal Securities
Schedule of Available for Sale Securities and Held to Maturity Securities [Line Items]
Held to maturity securities, Within One Year, Amortized Cost	3,270
Held to maturity securities, Within One Year, Fair Value	3,291
Held to maturity securities, After One, But Within Five Years, Amortized Cost	10,606
Held to maturity securities, After One, But Within Five Years, Fair Value	10,902
Held to maturity securities, After Five, But Within Ten Years, Amortized Cost	45,201
Held to maturity securities, After Five, But Within Ten Years, Fair Value	47,523
Held to maturity securities, After Ten Years, Amortized Cost	25,356
Held to maturity securities, After Ten Years, Fair Value	25,903
Held to maturity securities, Amortized Cost	84,433	75,208
Held to maturity securities, Fair Value	$ 87,619	$ 76,150

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