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Litigation and Contingencies (Details) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
	Mar. 31, 2021	Dec. 31, 2020
Commitments and Contingencies Disclosure [Abstract]
Average paid claim reduction due to curtailments (as a percent)	3.90%	3.60%
Maximum exposure associated with other discussions and legal proceedings	$ 43

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- Definition

Average paid claim reduction due to curtailments.

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- Definition

Estimated maximum exposure associated with other discussions and legal proceedings related to claims paying practices.

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No definition available.

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- References

No definition available.

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