CONSOLIDATED STATEMENTS OF OPERATIONS AND COMPREHENSIVE LOSS (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Sep. 30, 2016	Sep. 30, 2015
Income Statement [Abstract]
Accumulated other comprehensive loss reclassification for net unrealized gains	$ 4,892		$ 4,745
Unrealized change in investments, tax	4	$ (17)	1,621	$ (609)
Reclassification of net realized gains on investments, tax	$ (1,712)		$ (1,661)