Debt Securities Held to Maturity (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Dec. 31, 2018
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	$ 289,089	$ 262,143
Gross unrealized gains	7,412	73
Gross unrealized (losses)	(176)	(7,375)
Fair value	296,325	254,841
U.S. government and agency obligations
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	25,000	23,404
Gross unrealized gains	70	45
Gross unrealized (losses)	(142)	(208)
Fair value	24,928	23,241
Mortgage-backed securities and collateralized mortgage obligations
Schedule of Held-to-maturity Securities [Line Items]
Amortized cost	264,089	238,739
Gross unrealized gains	7,342	28
Gross unrealized (losses)	(34)	(7,167)
Fair value	$ 271,397	$ 231,600

Amount of investment in debt security measured at amortized cost (held-to-maturity).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
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-Subparagraph (b)
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Amount of accumulated unrecognized gain on investment in debt security measured at amortized cost (held-to-maturity).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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Amount of accumulated unrealized loss on investment in debt security measured at amortized cost (held-to-maturity).

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Fair value of investment in debt security measured at amortized cost (held-to-maturity).

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