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Subsequent Event (Details) - USD ($) $ in Thousands, shares in Millions	Jul. 01, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Assets		$ 3,970,739		$ 3,929,090
Citizens First
Subsequent Event [Line Items]
Assets			$ 472,100
Loans			377,900
Deposits			$ 381,800
Subsequent Event \| Citizens First
Subsequent Event [Line Items]
Shares of common stock issued for acquisition (in shares)	1.7
Total stock consideration paid	$ 50,100
Cash consideration paid	$ 15,500