Investments (Reclassifications of AOCI) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flow hedges—Currency/Interest rate
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Amount Reclassified from AOCI	$ 391	$ 232
Net unrealized investment gains (losses) on available-for-sale securities
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Amount Reclassified from AOCI	(2,537)	1,630
Total net unrealized investment gains (losses)
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Amount Reclassified from AOCI	(2,146)	1,862
Accumulated Other Comprehensive Income (Loss)
Reclassification Adjustment out of Accumulated Other Comprehensive Income on Derivatives [Line Items]
Amount Reclassified from AOCI	$ (2,146)	$ 1,862