[Line Items] for Legal Proceedings, Commitments and Contingencies, and Guarantees [Table]

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- Definition

Reduction To Pretax Operating Income Due To Interest Due To Policyholders On The Premium Rate Adjustments

+ References

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- Definition

Reduction to Earned Premium due to the Small Business Premium Rate Adjustment Contingency

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- Definition

The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=82913245&loc=d3e12069-110248

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- Definition

Amount of loss contingency liability.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 450
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82911808&loc=d3e14326-108349

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Legal Proceedings, Contingencies and Guarantees (Narrative) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017	Dec. 31, 2017
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Reduction to earned premium due to the small business premium rate adjustment contingency		$ 38
Reduction to pretax operating income due to interest due to policyholders on the premium rate adjustments	$ 1	$ 5
Guarantee Obligations
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	1,800
Indemnification Agreement
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	252
Guarantee agreement
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, maximum exposure, undiscounted	375
Guarantee and Indemnification
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Guarantor obligations, current carrying calue	5		$ 5
Insurance Premium Rate Adjustment \| Multi-Peril Package Product
Legal Proceedings, Commitments and Contingencies, and Guarantees [Line Items]
Loss contingency accrual	$ 60