Deferred Policy Acquisition Costs and Deferred Sales Inducements (Deferred Sales Inducements) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Movement in Deferred Sales Inducements [Roll Forward]
Balance at beginning of year	$ 1,292,341	$ 1,242,787	$ 1,227,328
Costs deferred during the year	337,787	306,659	385,123
Amortization	(253,113)	(87,157)	(71,781)
Effect of net unrealized gains/losses	498,865	(169,948)	(297,883)
Balance at end of year	$ 1,875,880	$ 1,292,341	$ 1,242,787