Acquisitions (Narrative) (Details) - USD ($)		9 Months Ended
	Feb. 28, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2018	Dec. 31, 2017
Business Acquisition [Line Items]
Share price	$ 35.70
Goodwill		$ 22,310,000		$ 22,310,000	$ 1,800,000
Universal Bancorp [Member]
Business Acquisition [Line Items]
Business acquisition, percentage of voting interests acquired	100.00%
Business acquisition, effective date of acquisition		Feb. 28, 2018
Business acquisition, name of acquired entity		Universal Bancorp ("Universal")
Business combination acquirer's shares issued per acquiree's single share	15.6
Business combination acquirer cash given per acquiree's single share	$ 250.00
Business acquisition, equity interest issued or issuable, number of shares	1,200,000
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable	$ 42,323,000
Total Loans	252,431,000
Contractual principal amount	257,000,000
Business acquisition, transaction costs	2,200,000
Core deposit intangible	4,545,000
Goodwill	$ 20,511,000
Finite Lived Intangible Asset Useful Life	15 years
Total purchase price	$ 61,322,000
Loans acquired		$ 144,721,000		$ 179,968,000
Credit adjustment	$ 4,600,000
Revenue, pro forma			$ 9,100,000
Earnings, pro forma			$ 4,200,000