Separate Accounts, Death Benefits and Other Insurance Benefit Features and Embedded Product Derivatives - Narrative (Details) (USD $)	3 Months Ended
	Mar. 31, 2015	Mar. 31, 2014	Dec. 31, 2014
Insurance [Abstract]
Assets fair value and carrying amount	$ 2,700,000,000		$ 2,600,000,000
Fair value of embedded derivatives	166,900,000		153,900,000
Embedded derivatives gains and (losses) recognized in earnings	$ (10,200,000)	$ (12,900,000)