Sales Inducements (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Changes in Deferred Sales Inducement Activity:
Deferred asset, beginning of period	$ 60.9	$ 49.7	$ 20.4
Sales inducements deferred	10.7	15.4	48.3
Amortization charged to income	(7.3)	(6.8)	(4.9)
Offsets to net unrealized investment gains or losses included in AOCI	11.4	2.6	(14.1)
Deferred asset, end of period	$ 75.7	$ 60.9	$ 49.7