Parent Corporation Only Financial Statements (Details) - Condensed Statements of Income - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2018	Dec. 31, 2017		Dec. 31, 2016
Income:
Dividend income from subsidiaries									$ 2,012	$ 1,421		$ 1,410
Other income									607	736	[1]
Net Income	$ 18,672	$ 19,902	$ 17,527	$ 4,251	$ 10,580	$ 13,077	$ 7,683	$ 11,880	60,352	43,220		31,082
Parent Company [Member]
Income:
Dividend income from subsidiaries									16,700	13,000		12,400
Other income									1,618	13		8
Total Income									18,318	13,013		12,408
Expenses									(7,201)	(3,251)		(3,252)
Income before equity in undistributed earnings of subsidiaries									11,117	9,762		9,156
Equity in undistributed earnings of subsidiaries									49,235	33,458		21,926
Net Income									$ 60,352	$ 43,220		$ 31,082

[1] The Company elected the modified retrospective approach of adoption; therefore, prior period balances are presented under legacy GAAP and may not be comparable to current year presentation.