Subsequent Events (Details) - Subsequent Event - Plaza Bancorp $ / shares in Units, $ in Millions	Nov. 01, 2017 USD ($) bank $ / shares shares
Subsequent Event [Line Items]
Number of branches | bank	7
Total assets acquired	$ 1,300.0
Loans, gross	1,100.0
Deposits	$ 1,100.0
Equity issued (shares)	0.2000
Number of shares of common stock issued as consideration | shares	6,049,447
Company's common stock value (usd per share) | $ / shares	$ 40.40
Total transaction consideration value	$ 251.0
Aggregate cash for fractional shares and consideration payable	$ 6.5