Deferred Acquisition Costs ("DAC"), Value Of Business Acquired ("VOBA") And Other Intangible Assets (Balances Of Unlocking On DAC And VOBA) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	9 Months Ended
Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Deferred Acquisition Costs, Value Of Business Acquired And Other Intangible Assets Disclosures [Abstract]
Decrease to DAC and VOBA	$ 0.3	$ 0.2	$ 1.4	$ 0.8

Total increase (decrease) in deferred acquisition costs and value of business acquired as a result of changes in the key assumptions used to reflect the Company's best estimate of expected gross profit. Key assumptions include persistency, interest rates, stock market performance, capital gains and losses, claim termination rates, and amount of business in force. Because actual results and trends related to these assumptions vary from those assumed, the Company revises these assumptions annually to reflect its current best estimate of expected gross profits. As a result of this process, known as "unlocking," the cumulative balances of deferred acquisition costs and value of business acquired are adjusted with an offsetting benefit or charge to income to reflect changes in the period of revision.

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration