Securities, Available-for-sale Securities (Details) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Available-for-sale [Abstract]
Amortized cost	$ 625,914	$ 593,945
Gross unrealized gains	12,435	7,860
Gross unrealized losses	(4,870)	(1,961)
Fair value	633,479	599,844
U.S. Treasury and Government Agencies [Member]
Available-for-sale [Abstract]
Amortized cost	159,199	171,250
Gross unrealized gains	1,009	476
Gross unrealized losses	(337)	(576)
Fair value	159,871	171,150
State and Political Subdivisions [Member]
Available-for-sale [Abstract]
Amortized cost	96,171	99,403
Gross unrealized gains	3,068	2,941
Gross unrealized losses	(43)	(37)
Fair value	99,196	102,307
U.S. Government Sponsored Agency Mortgage-backed Securities [Member]
Available-for-sale [Abstract]
Amortized cost	313,979	291,874
Gross unrealized gains	8,358	4,443
Gross unrealized losses	(1,294)	(1,072)
Fair value	321,043	295,245
Other Debt Securities [Member]
Available-for-sale [Abstract]
Amortized cost	56,565	31,418
Gross unrealized gains	0	0
Gross unrealized losses	(3,196)	(276)
Fair value	$ 53,369	$ 31,142

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amount, before tax, of unrealized loss in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

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