Closed Block - Results of Operations (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Revenues
Premiums	$ 24	$ 58	$ 64
Net investment income	84	86	86
Investment related gains (losses)	42	(124)	110
Total revenues	150	20	260
Benefits and Expenses
Future policy and other policy benefits	107	(24)	212
Dividends to policyholders	40	45	45
Total benefits and expenses	147	21	257
Contribution from (to) AmerUs Closed Block before income taxes	3	(1)	3
Federal income taxes funded by the Closed Block	3	1	6
Contribution to AmerUs Closed Block, net of income taxes	$ 0	$ (2)	$ (3)

Amount of benefits, claims and expenses that are related to an insurance entity's segregated group of participating or dividend-paying policies and contracts along with the assets allocated to them (known as a closed block). Includes, but is not limited to, death benefits, matured endowments, participating dividends, general expenses and deferred acquisition costs related to the closed block.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

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- Definition

The amount of income tax expense or benefit allocated to the operations of the closed block for the period.

+ References

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- Definition

Income for the period from the investments allocated to an insurance entity's segregated group of participating or dividend-paying policies and contracts (known as a closed block), net of investment expenses, which are typically reported in a table of closed block operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(5)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

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- Definition

Amount of net income (loss) from operations of the closed block.

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- Definition

An expense for the period for estimated policy claims in an insurance entity's segregated group of participating or dividend-paying policies and contracts along with the assets allocated to them (known as a closed block), as typically reported in a table of closed block operations as part of summarized financial data.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (a)(5),(b)(7)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

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- Definition

An expense for the period representing distributions paid or accrued for the segregated group of participating or dividend-paying policies and contracts along with the assets allocated to them (known as a closed block), which may be presented in a table of closed block operations as part of summarized financial data.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(8)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

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- Definition

For the segregated group of participating or dividend-paying policies and contracts along with the assets allocated to them (known as a closed block), revenue for the period from insurance policy premiums; typically included in a table of closed block operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(4)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

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- Definition

Gains and losses realized for the period from the investments allocated to an insurance entity's segregated group of participating or dividend-paying policies and contracts (known as a closed block).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 805
-Section 50
-Paragraph 3
-Subparagraph (b)(6)
-URI http://asc.fasb.org/extlink&oid=6487222&loc=d3e30806-158569

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The revenues less expenses from operations of the closed block during the period, before income taxes allocated thereto.

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- Definition

Total revenues from an insurance company's segregated group of participating or dividend-paying policies and contracts along with the assets allocated to them (known as a closed block).

+ References

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