- Acquisitions (Details) $ / shares in Units, $ in Thousands		3 Months Ended		9 Months Ended
	Jan. 04, 2019 USD ($) Branch $ / shares shares	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2018 USD ($)
Business Acquisition [Line Items]
Merger related expenses		$ 0	$ 0	$ 3,178	$ 0
Highlands Bancorp, Inc.
Business Acquisition [Line Items]
Number of bank branches operated | Branch	4
Business acquisition, conversion, shares issued | shares	1.015
Consideration paid through common stock | shares	2,837,524
Stock option payout price per share (in dollars per share) | $ / shares	$ 14.71
Average strike price (in dollars per share) | $ / shares	$ 8.09
Cash paid for redemption of stock options	$ 797
Goodwill, period increase (decrease)				447,000
Identifiable intangible assets	$ 3,728
Useful life	10 years
Merger related expenses		$ 0		$ 3,200