VOBA And Other Intangible Assets VOBA and Other Intangible Assets (Estimated Amortization of VOBA) (Details) - VOBA $ in Millions	12 Months Ended
Dec. 31, 2017 USD ($)
Finite-Lived Intangible Assets [Line Items]
2018	$ 7.1
2019	6.6
2020	6.3
2021	0.8
2022	0.7
Thereafter	2.9
Total	$ 24.4

Expected Amortization Expense of Ending Present Value of Future Insurance Profits, Thereafter

No definition available.

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- Definition

Expected amortization expense in the fifth year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 20
-Section S99
-Paragraph 2
-Subparagraph (3)
-URI http://asc.fasb.org/extlink&oid=27015749&loc=d3e569990-122904

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- Definition

Expected amortization expense in the fourth year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

+ Details

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- Definition

Expected amortization expense in the first year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

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- Definition

Expected amortization expense in the third year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

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- Definition

Expected amortization expense in the second year after the balance sheet date of the present value of the future profits of long-duration contracts acquired in a purchase of an insurance enterprise.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Amount after amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

+ 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)(1)
-URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16323-109275

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