Balance Sheets (USD $) In Millions, unless otherwise specified	Dec. 31, 2014	Sep. 30, 2014	Jun. 30, 2014	Mar. 31, 2014	Dec. 31, 2013	Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
ASSETS:
Available-for-sale debt securities, at fair value (amortized cost of $4,060.9 and $3,390.6)	$ 4,221.8	$ 4,049.3	$ 3,829.6	$ 3,578.0	$ 3,416.1	$ 3,245.8	$ 3,154.8	$ 3,049.9
Available-for-sale equity securities, at fair value (cost of $28.4 and $12.1)	28.7	27.7	11.9	11.6	11.2	7.3	7.8	5.6
Short-term investments	79.8	0	189.8	190.9	81.0	55.0	165.0	224.9
Limited partnerships and other investments	12.5	10.9	10.9	10.7	10.5	10.3	7.2	5.7
Policy loans, at unpaid principal balances	68.1	67.5	66.3	67.3	66.1	65.6	62.8	61.5
Derivative instruments	157.5	134.9	159.3	156.7	225.3	175.4	183.6	175.8
Fair value investments	46.7	47.1	47.6	48.2	48.6	53.1	48.8	46.5
Total investments	4,615.1	4,337.4	4,315.4	4,063.4	3,858.8	3,612.5	3,630.0	3,569.9
Cash and cash equivalents	162.3	206.1	154.9	140.9	181.0	218.1	123.9	116.2	83.1	49.5
Accrued investment income	33.2	34.7	29.5	32.0	27.3	29.7	25.7	29.0
Reinsurance recoverable	464.6	452.6	451.5	467.8	494.3	485.3	456.1	444.7
Deferred policy acquisition costs	430.9	451.5	441.5	454.8	470.1	458.3	461.9	430.6
Deferred income taxes, net	13.1	12.8	11.1	17.9	27.8	25.7	25.5	13.4
Receivable from related parties	5.5	6.4	13.6	13.2	2.6	2.1	6.0	0
Other assets	158.3	204.1	174.0	181.4	204.1	222.1	206.3	183.7
Separate account assets	1,757.5	1,816.3	1,951.0	1,979.3	2,052.7	2,049.5	2,021.3	2,109.5
Total assets	7,640.5	7,521.9	7,542.5	7,350.7	7,318.7	7,103.3	6,956.7	6,897.0
LIABILITIES:
Policy liabilities and accruals	2,067.0	1,974.8	1,957.6	1,926.1	1,882.9	1,970.9	1,923.7	1,926.4
Policyholder deposit funds	3,306.9	3,181.2	3,019.3	2,890.9	2,775.2	2,671.3	2,574.6	2,474.2
Indebtedness due to affiliate	30.0	30.0	30.0	30.0	30.0	0	0	0
Payable to related parties	7.6	11.3	15.3	10.8	14.1	12.8	18.3	15.5
Other liabilities	167.7	119.9	178.8	148.8	182.4	144.8	161.4	115.9
Separate account liabilities	1,757.5	1,816.3	1,951.0	1,979.3	2,052.7	2,049.5	2,021.3	2,109.5
Total liabilities	7,336.7	7,133.5	7,152.0	6,985.9	6,937.3	6,849.3	6,699.3	6,641.5
COMMITMENTS AND CONTINGENT LIABILITIES (Note 17)
STOCKHOLDER’S EQUITY:
Common stock, $5,000 par value: 1,000 shares authorized; 500 shares issued	2.5	2.5	2.5	2.5	2.5	2.5	2.5	2.5
Additional paid-in capital	862.2	847.2	847.2	847.2	847.2	802.2	802.2	802.2
Accumulated other comprehensive income (loss)	4.0	8.7	15.6	(14.1)	(12.7)	4.5	(6.3)	(3.7)	8.8
Retained earnings (accumulated deficit)	(564.9)	(470.0)	(474.8)	(470.8)	(455.6)	(555.2)	(541.0)	(545.5)
Total stockholder’s equity	303.8	388.4	390.5	364.8	381.4	254.0	257.4	255.5
Total liabilities and stockholder’s equity	$ 7,640.5	$ 7,521.9	$ 7,542.5	$ 7,350.7	$ 7,318.7	$ 7,103.3	$ 6,956.7	$ 6,897.0