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Derivative Financial Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018
Interest Rate Lock Commitments
Derivative Financial Instruments
Aggregate notional amount	$ 135,600		$ 135,600		$ 27,200
Forward Sales Commitments
Derivative Financial Instruments
Aggregate notional amount	189,500		189,500		48,600
Interest rate lock commitments and forward sales commitments
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Net gains (losses)	(51)	$ 80	(111)	$ (273)
Interest rate lock commitments and forward sales commitments \| Non-interest income
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Gross gains	1,655	641	4,662	2,396
Interest rate lock commitments and forward sales commitments \| Non-interest expense
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Gross (losses)	(1,706)	(561)	(4,773)	(2,669)
Interest rate lock commitments and forward sales commitments \| Other assets
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	1,182		1,182		624
Interest rate lock commitments and forward sales commitments \| Other liabilities
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	1,707		1,707		1,205
Interest rate swap
Derivative Financial Instruments
Aggregate notional amount	511,400		511,400		243,700
Variable rate, commercial loans that are supported by the interest rate swap contracts	255,700		255,700		121,800
Derivative cash pledged					1,000
Derivative securities pledged	18,600		18,600
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Net gains (losses)	0	0	0	0
Interest rate swap \| Non-interest income
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Gross gains	4,695	724	15,205	2,167
Interest rate swap \| Non-interest expense
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Gross (losses)	(4,695)	$ (724)	(15,205)	$ (2,167)
Interest rate swap \| Cash Flow Hedging
Derivative Financial Instruments
Aggregate notional amount	$ 70,000		$ 70,000
Weighted average fixed pay rates	1.80%		1.80%
Weighted average receive rates	2.12%		2.12%
Weighted average maturity			4 years 1 month 9 days
Unrealized gains (losses)			$ 592
Unrealized gain to be reclassified from OCI to interest expense during next twelve months			100
Gross gains and losses on derivative assets and liabilities recorded in Consolidated Statements of Income
Amount of ineffectiveness included in net income	$ 0
Interest rate swap \| Other assets
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other assets	16,643		16,643		1,438
Interest rate swap \| Other liabilities
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	16,643		16,643		$ 1,438
Interest rate swap \| Other liabilities \| Cash Flow Hedging
Fair values of derivative assets and liabilities recorded in consolidated balance sheets
Fair value recorded in other liabilities	800		800
Interest rate contract
Derivative Financial Instruments
Derivative cash pledged	800		800
Interest rate contract \| Cash Flow Hedging
Derivative Financial Instruments
Amount of (gain) loss recognized in OCI (effective portion)	(598)		(598)
Amount of (gain) loss reclassified from OCI to interest income	$ (6)		$ (6)