CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Consolidated Statements Of Comprehensive Income
Net Income	$ 6,050	$ 7,799	$ 7,474	$ 7,602	$ 6,040	$ 7,685	$ 6,882	$ 7,201	$ 28,925	$ 27,808	$ 26,582
Other Comprehensive Income (loss), net of tax: Unrealized Gain (loss) on investments, net of tax expense of $283 in 2015 and net of tax benefit of $131 in 2014									528	(245)	0
Comprehensive Income									$ 29,453	$ 27,563	$ 26,582