Investment Securities - Reconciliation (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 985,541	$ 812,174
Gross Unrealized Gains	3,285	5,483
Gross Unrealized Losses	12,731	7,127
Fair Value	976,095	810,530
U.S. Treasury and U.S. Government-sponsored agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	101,595	13,460
Gross Unrealized Gains	155	6
Gross Unrealized Losses	147	24
Fair Value	101,603	13,442
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	158,461	247,358
Gross Unrealized Gains	1,209	3,720
Gross Unrealized Losses	806	1,063
Fair Value	158,864	250,015
Residential mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	337,295	282,724
Gross Unrealized Gains	426	422
Gross Unrealized Losses	6,119	2,935
Fair Value	331,602	280,211
Commercial mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	338,250	219,696
Gross Unrealized Gains	1,035	444
Gross Unrealized Losses	5,524	3,061
Fair Value	333,761	217,079
Collateralized loan obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost		4,561
Gross Unrealized Gains		19
Gross Unrealized Losses		0
Fair Value		4,580
Corporate obligations
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	25,662	16,594
Gross Unrealized Gains	36	220
Gross Unrealized Losses	135	44
Fair Value	25,563	16,770
Other securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	24,278	27,781
Gross Unrealized Gains	424	652
Gross Unrealized Losses	0	0
Fair Value	$ 24,702	$ 28,433

Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt securities classified as available-for-sale.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
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