Reinsurance - Other Reinsurance Activity (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended				9 Months Ended
	Sep. 30, 2013		Sep. 30, 2012		Sep. 30, 2013		Sep. 30, 2012
Direct Business and Reinsurance:
Direct premiums	$ 18.2		$ 16.7		$ 60.3		$ 52.8
Premiums ceded to non-affiliate reinsurers	(15.1)	[1]	(15.9)	[1]	(49.0)	[1]	(49.6)	[1]
Premiums	3.1		0.8		11.3		3.2
Direct policy benefits incurred	87.2		75.0		184.6		214.4
Policy benefits assumed from non-affiliate reinsureds	0		1.0		0		2.5
Policy benefits ceded to:
Affiliate reinsurers	0		(6.9)		(9.0)		(9.2)
Non-affiliate reinsurers	(50.5)		(20.4)		(84.5)		(94.1)
Policy benefits ceded to reinsurers	(50.5)		(27.3)		(93.5)		(103.3)
Premiums paid to:
Affiliate reinsurers	5.5		5.5		16.6		15.0
Non-affiliate reinsurers	17.1		18.7		27.8		42.4
Premiums paid to reinsurers	22.6	[2]	24.2	[2]	44.4	[2]	57.4	[2]
Policy benefits	59.3	[3]	72.9	[3]	135.5	[3]	171.0	[3]
Changes in reserves, interest credited to policyholders and withdrawals amount	$ 32.5		$ 84.5		$ 136.2		$ 139.8

[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 $32.5 million and $84.5 million net of reinsurance, for the three months ended September 30, 2013 and 2012, respectively, and $136.2 million and $139.8 million, net of reinsurance, for the nine months ended September 30, 2013 and 2012, respectively.