Reinsurance - Other Resinsurance Activity (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012		Dec. 31, 2011
Direct Business and Reinsurance:
Direct premiums	$ 80.9		$ 79.2		$ 77.1
Premiums ceded to non-affiliate reinsurers	(67.0)	[1]	(70.7)	[1]	(74.8)	[1]
Premiums	13.9		8.5		2.3
Direct policy benefits incurred	258.5		281.4		161.4
Policy benefits assumed from non-affiliate reinsureds	0.2		1.0		3.8
Affiliate reinsurers	(18.0)		(13.7)		(5.3)
Non-affiliate reinsurers	(119.5)		(114.7)		(86.0)
Policy benefits ceded to reinsurers	(137.5)		(128.4)		(91.3)
Premiums paid to: Affiliate reinsurers	22.3		20.1		19.7
Premiums paid to: Non-affiliate reinsurers	44.4		60.8		58.7
Premiums paid to reinsurers	66.7	[2]	80.9	[2]	78.4	[2]
Policy benefits	187.9	[3]	234.9	[3]	152.3	[3]
Direct life insurance in-force	58,198.8		62,701.8		68,205.1
Life insurance in-force assumed from reinsureds	93.2		78.5		66.1
Life insurance in-force ceded to: Affiliate reinsurers	(1,622.9)		(1,859.3)		(2,520.7)
Life insurance in-force ceded to: Non-affiliate reinsurers	(42,957.9)		(46,950.4)		(49,800.1)
Life insurance in-force ceded to reinsurers	(44,580.8)		(48,809.7)		(52,320.8)
Life insurance in-force	13,711.2		13,970.6		15,950.4
Percentage of amount assumed to net insurance in-force	0.70%		0.60%		0.40%
Changes in reserves, interest credited to policyholders and withdrawals amount	$ 98.6		$ 161.9		$ 150.3

[1] Primarily represents premiums ceded to reinsurers related to term insurance policies.

[2] For universal life and variable universal life contracts, premiums paid to reinsurers are reflected within policy benefits. See Note 2 to these financial statements for additional information regarding significant accounting policies.

[3] Policy benefit amounts above exclude changes in reserves, interest credited to policyholders and other items, which total $98.6 million, $161.9 million and $150.3 million, net of reinsurance, for the years ended December 31, 2013, 2012 and 2011, respectively.