Investments (Balance of and Changes in AOCI Components) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2015	Sep. 30, 2014	Sep. 30, 2015	Sep. 30, 2014	Dec. 31, 2014	Dec. 31, 2013
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning			$ 84,622
Income tax benefit (expense)	$ 14,953	$ (14,765)	(4,615)	$ (41,605)
Balance, ending	62,550		62,550		$ 84,622
Foreign Currency Translation Adjustment
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning			(30)	10	10
Change in other comprehensive income before reclassifications			(39)	(33)
Amounts reclassified from AOCI			0	0
Income tax benefit (expense)			14	12
Balance, ending	(55)	(11)	(55)	(11)	(30)	$ 10
Net Unrealized Investment Gains (Losses)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning			84,652	70,857	70,857
Change in other comprehensive income before reclassifications			(29,267)	23,390
Amounts reclassified from AOCI	252		(4,652)	(4,776)
Income tax benefit (expense)			11,872	(6,516)
Balance, ending	62,605	82,955	62,605	82,955	84,652	70,857
Cash Flow Hedge Gain (Loss) To AOCI			13,400	(1,000)	5,000	(4,000)
Total Accumulated Other Comprehensive Income (Loss)
AOCI Attributable to Parent, Net of Tax [Roll Forward]
Balance, beginning			84,622	70,867	70,867
Change in other comprehensive income before reclassifications			(29,306)	23,357
Amounts reclassified from AOCI	252		(4,652)	(4,776)
Income tax benefit (expense)			11,886	(6,504)
Balance, ending	$ 62,550	$ 82,944	$ 62,550	$ 82,944	$ 84,622	$ 70,867