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Life and Annuity Benefits Life and Annuity Benefits (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Dec. 31, 2019
Liability for Future Policy Benefit, before Reinsurance [Abstract]
Increase in life and annuity benefits	$ 22.7	$ 36.0	$ 35.6	$ 61.8
Cumulative adjustment to life and annuity benefits	$ 87.0		$ 87.0		$ 51.4

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- Definition

The adjustment to life and annuity benefits during the period attributable to the change in unrealized gains on the underlying investment portfolio during the period.

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No definition available.

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- Definition

The cumulative adjustment to life and annuity benefits attributable to unrealized gains on the underlying investment portfolio.

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No definition available.

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No definition available.

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