DAC, VOBA, DSI, and DFEL (Estimated Future Amortization of VOBA) (Details) $ in Millions	Dec. 31, 2017 USD ($)
Estimated future amortization of VOBA, net of interest [Abstract]
2018	$ 49
2019	51
2020	65
2021	65
2022	$ 61

No definition available.

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- Definition

Amount of amortization expense expected to be recognized during fifth fiscal year following latest fiscal year for present value of future profits of insurance contract acquired in business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6918812&loc=d3e30762-158568

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- Definition

Amount of amortization expense expected to be recognized during fourth fiscal year following latest fiscal year for present value of future profits of insurance contract acquired in business combination.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6918812&loc=d3e30762-158568

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 30
-Section 50
-Paragraph 2
-Subparagraph (a)(3)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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- Definition

Amount of amortization expense expected to be recognized during next fiscal year following latest fiscal year for present value of future profits of insurance contract acquired in business combination.

+ References

+ Details

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- Definition

Amount of amortization expense expected to be recognized during third fiscal year following latest fiscal year for present value of future profits of insurance contract acquired in business combination.

+ References

+ Details

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- Definition

Amount of amortization expense expected to be recognized during second fiscal year following latest fiscal year for present value of future profits of insurance contract acquired in business combination.

+ References

+ Details

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