Restatement and Amendment of Previously Reported Financial Information Summary of Correction of Errors, Cash Flow (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended		12 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012
OPERATING ACTIVITIES:
Net income (loss)	$ (20.4)	$ (22.5)
Net realized investment (gains) losses	17.4	2.5
Policy acquisition costs deferred	(17.2)	(24.0)
Policy acquisition cost amortization	14.0	40.7
Interest credited	18.4	16.0
Equity in earnings of limited partnerships and other investments	0.8	(0.3)
Change in:
Accrued investment income	(6.8)	(6.2)
Deferred income taxes, net	0	(1.4)
Receivables	6.4	27.0
Reinsurance recoverable	(17.0)	(13.6)
Policy liabilities and accruals	(55.5)	(56.0)
Due to/from affiliate	4.5	9.0
Other operating activities, net	3.6	13.0
Cash provided by (used for) operating activities	(51.8)	(15.8)
Purchases of:
Available-for-sale debt securities	(155.0)	(211.0)
Short-term investments	(224.8)	(60.0)
Derivative instruments	(35.1)	(19.0)
Fair value investments	(9.8)	0
Sales, repayments and maturities of:
Proceeds from sales	0.2		160.0
Derivative instruments	7.7	1.8
Fair value investments	1.7	1.1
Contributions to limited partnerships	(0.3)	(0.6)
Distributions from limited partnerships	0	0.2
Policy loans, net	0.2	2.4
Other investing activities, net	0.1	0
Cash provided by (used for) investing activities	(97.0)	(188.5)
FINANCING ACTIVITIES:
Policyholder deposit fund deposits	247.2	289.2
Policyholder deposit fund withdrawals	(135.3)	(139.8)
Net transfers to/from separate accounts	70.0	77.6
Cash provided by (used for) financing activities	181.9	227.0
Change in cash and cash equivalents	33.1	22.7
Cash and cash equivalents, beginning of year	83.1	49.5	49.5
Cash and cash equivalents, end of year	116.2	72.2	83.1
Non-Cash Transactions During the Year
Income taxes paid (refunded)	(3.7)	(0.9)
Investment exchanges	19.0	7.7
Corrections of Errors
OPERATING ACTIVITIES:
Net income (loss)		(25.4)
Net realized investment (gains) losses		(5.3)
Policy acquisition costs deferred		4.9
Policy acquisition cost amortization		12.0
Interest credited		16.0
Equity in earnings of limited partnerships and other investments		(0.2)
Change in:
Accrued investment income		(0.8)
Deferred income taxes, net		9.6
Receivables		(0.2)
Policy liabilities and accruals		(81.7)
Due to/from affiliate		9.0
Other operating activities, net		(4.9)
Cash provided by (used for) operating activities		(67.0)
Purchases of:
Available-for-sale debt securities		9.4
Derivative instruments		0
Fair value investments		0
Other investments		0.6
Sales, repayments and maturities of:
Proceeds from sales		(10.4)
Derivative instruments		0
Fair value investments		1.1
Other investments		(0.2)
Contributions to limited partnerships		(0.6)
Distributions from limited partnerships		0.2
Policy loans, net		0.6
Cash provided by (used for) investing activities		0.7
FINANCING ACTIVITIES:
Policyholder deposit fund deposits		74.4
Policyholder deposit fund withdrawals		(86.3)
Net transfers to/from separate accounts		77.6
Cash provided by (used for) financing activities		65.7
Change in cash and cash equivalents		(0.6)
Cash and cash equivalents, beginning of year		(18.0)	(18.0)
Cash and cash equivalents, end of year		(18.6)
Non-Cash Transactions During the Year
Income taxes paid (refunded)		(0.9)
Investment exchanges		7.7
As previously reported
OPERATING ACTIVITIES:
Net income (loss)		2.9
Net realized investment (gains) losses		7.8
Policy acquisition costs deferred		(28.9)
Policy acquisition cost amortization		28.7
Interest credited		0
Equity in earnings of limited partnerships and other investments		(0.1)
Change in:
Accrued investment income		(5.4)
Deferred income taxes, net		(11.0)
Receivables		13.6
Policy liabilities and accruals		25.7
Due to/from affiliate		0
Other operating activities, net		17.9
Cash provided by (used for) operating activities		51.2
Purchases of:
Available-for-sale debt securities		(280.4)
Derivative instruments		(19.0)
Fair value investments		0
Other investments		(0.6)
Sales, repayments and maturities of:
Proceeds from sales		107.0
Derivative instruments		1.8
Fair value investments		0
Other investments		0.2
Contributions to limited partnerships		0
Distributions from limited partnerships		0
Policy loans, net		1.8
Cash provided by (used for) investing activities		(189.2)
FINANCING ACTIVITIES:
Policyholder deposit fund deposits		214.8
Policyholder deposit fund withdrawals		(53.5)
Net transfers to/from separate accounts		0
Cash provided by (used for) financing activities		161.3
Change in cash and cash equivalents		23.3
Cash and cash equivalents, beginning of year		67.5	67.5
Cash and cash equivalents, end of year		90.8
Non-Cash Transactions During the Year
Income taxes paid (refunded)		0
Investment exchanges		0
As restated and amended
OPERATING ACTIVITIES:
Net income (loss)		(22.5)
Net realized investment (gains) losses		2.5
Policy acquisition costs deferred		(24.0)
Policy acquisition cost amortization		40.7
Interest credited		16.0
Equity in earnings of limited partnerships and other investments		(0.3)
Change in:
Accrued investment income		(6.2)
Deferred income taxes, net		(1.4)
Receivables		13.4
Policy liabilities and accruals		(56.0)
Due to/from affiliate		9.0
Other operating activities, net		13.0
Cash provided by (used for) operating activities		(15.8)
Purchases of:
Available-for-sale debt securities		(271.0)
Derivative instruments		(19.0)
Fair value investments		0
Other investments		0
Sales, repayments and maturities of:
Proceeds from sales		96.6
Derivative instruments		1.8
Fair value investments		1.1
Other investments		0
Contributions to limited partnerships		(0.6)
Distributions from limited partnerships		0.2
Policy loans, net		2.4
Cash provided by (used for) investing activities		(188.5)
FINANCING ACTIVITIES:
Policyholder deposit fund deposits		289.2
Policyholder deposit fund withdrawals		(139.8)
Net transfers to/from separate accounts		77.6
Cash provided by (used for) financing activities		227.0
Change in cash and cash equivalents		22.7
Cash and cash equivalents, beginning of year		49.5	49.5
Cash and cash equivalents, end of year		72.2
Non-Cash Transactions During the Year
Income taxes paid (refunded)		(0.9)
Investment exchanges		$ 7.7