Condensed Consolidated Statements Of Comprehensive Income (Parenthetical) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2013	Sep. 30, 2012	Sep. 30, 2013	Sep. 30, 2012
Condensed Consolidated Statements Of Comprehensive Income [Abstract]
Unrealized (loss) gain on investments, tax (benefit) expense	$ 51	$ 33	$ 84	$ 66
Unrealized gain, tax expense	(1,512)	(1,294)	1,278	(1,235)
Reclassification adjustment for gains included in net income, tax expense	$ 329	$ 395	$ 542	$ 1,434