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Number of shares of equity interests issued or issuable to acquire entity.

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Business Combinations (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Sep. 30, 2019	Mar. 31, 2019	Dec. 31, 2018
Subsequent Event [Line Items]
Assets		$ 3,895,524	$ 3,929,090
Citizens First
Subsequent Event [Line Items]
Assets			476,000
Loans			372,000
Deposits			$ 389,000
Subsequent Event \| Scenario, Forecast \| Citizens First
Subsequent Event [Line Items]
Shares of common stock issued for acquisition (in shares)	1,700,000.0
Cash consideration	$ 16,000
Closing price of common shares (in usd per share)	$ 31.59
Aggregate indicated value of acquisition transaction	$ 68,200