Subsequent Events (Details) - Bank of Rio Vista [Member] - USD ($) $ in Millions		9 Months Ended
Oct. 10, 2018	Oct. 10, 2018	Sep. 30, 2018
Acquisitions [Abstract]
Total ownership of shares (in shares)			1,586
Percentage of ownership interests acquired			39.65%
Total price paid for common shares			$ 12.0
Subsequent Event [Member]
Acquisitions [Abstract]
Total ownership of shares (in shares)	2,414	2,414
Percentage of ownership interests acquired	60.35%	60.35%
Total price paid for common shares	$ 28.7	$ 40.7

Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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