Securities - AFS and HTM, Amortized Cost and FV (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Available for sale
Amortized cost	$ 945,156		$ 899,817
Unrealized Gains	28,219		12,702
Unrealized Losses	(1,057)		(1,026)
Fair Value	972,318		911,493
Held to maturity
Amortized cost	355,110		386,326
Unrealized Gains	14,676		4,354
Unrealized Losses	(172)		(1,750)
Held to maturity, fair value	369,614		388,930
Equity Securities
Equity, at fair value	107		166
Recognized net gain (loss) on equity securities	(100)	$ (100)
Bonds
Available for sale
Amortized cost	88,299		84,590
Unrealized Gains	1,437		1,049
Unrealized Losses			(64)
Fair Value	89,736		85,575
Held to maturity
Amortized cost			24,020
Unrealized Gains			10
Unrealized Losses			(35)
Held to maturity, fair value			23,995
Residential Mortgage Backed Securities
Available for sale
Amortized cost	415,399		430,514
Unrealized Gains	14,435		6,662
Unrealized Losses			(147)
Fair Value	429,834		437,029
Held to maturity
Amortized cost	16,809		17,776
Unrealized Gains	676		295
Held to maturity, fair value	17,485		18,071
Commercial mortgage-backed securities
Available for sale
Amortized cost	11,436		11,488
Unrealized Gains	967		543
Fair Value	12,403		12,031
Held to maturity
Amortized cost	160,113		161,624
Unrealized Gains	10,405		2,810
Unrealized Losses			(655)
Held to maturity, fair value	170,518		163,779
Collateralized Mortgage Obligations
Available for sale
Amortized cost	385,409		333,256
Unrealized Gains	9,634		3,175
Unrealized Losses	(1,057)		(815)
Fair Value	393,986		335,616
Held to maturity
Amortized cost	106,926		113,894
Unrealized Gains	2,260		226
Unrealized Losses	(37)		(904)
Held to maturity, fair value	109,149		113,216
States and political subdivisions
Available for sale
Amortized cost	44,613		39,969
Unrealized Gains	1,746		1,273
Fair Value	46,359		41,242
Held to maturity
Amortized cost	71,262		69,012
Unrealized Gains	1,335		1,013
Unrealized Losses	(135)		(156)
Held to maturity, fair value	$ 72,462		$ 69,869

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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