Condensed Consolidated Statements Of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014
Condensed Consolidated Statements Of Comprehensive Income [Abstract]
Unrealized gain on investments, tax expense (benefit)	$ (60)	$ (23)	$ (29)	$ (19)
Unrealized (loss) gain, tax (benefit) expense	1,030	2,809	2,882	1,796
Reclassification adjustment for losses (gains) included in net income, tax benefit (expense)	$ (1,374)	$ (67)	$ (4,079)	$ 24