Investments (HTM Fixed Income Securities by Contractual Maturity) (Details) - USD ($) $ in Thousands	Sep. 30, 2015	Dec. 31, 2014
Schedule of Held-to-maturity Securities [Line Items]
Due in one year or less carrying value	$ 102,507
Due after one year through five years carrying value	116,833
Due after five years through 10 years carrying value	10,529
Carrying Value	229,869	$ 318,137
Due in one year or less fair value	103,945
Due after one year through five years fair value	123,960
Due after five years through 10 years fair value	12,483
HTM, Fair Value	$ 240,388	$ 333,961