Fair Value - Narrative (Details) - USD ($)	12 Months Ended
Dec. 31, 2016	Dec. 31, 2015
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Assets, Level 1 to Level 2 transfers	$ 0	$ 0
Assets, Level 2 to Level 1 transfers	0	0
Liabilities, Level 1 to Level 2 transfers	0	0
Liabilities, Level 2 to Level 1 transfers	$ 0	0
Fixed Maturity Securities \| Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	4.00%
Fixed Maturity Securities \| Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Discount rate	8.00%
Future Policy Benefits \| AmerUs Closed Block
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Target surplus, percentage of statutory reserves	3.85%
Future Policy Benefits \| ILICO Closed Block and Life Benefits
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Cost of capital assumption, percentage of required capital	9.00%
Discount rate, margin	9.42%
Discount rate, non-performance risk	0.26%
Interest Sensitive Contract Liabilities \| Universal Life
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Risk margin	0.09%
Mortgage Loans
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value option, loans, 90 days or more past due	$ 0	$ 0

Fair Value Inputs, Cost of Capital Assumption, Percentage of Required Capital

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- Definition

Fair Value Inputs, Discount Rate, Risk Margin

+ References

No definition available.

+ Details

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- Definition

Fair Value Inputs, Target Surplus, Percentage of Statutory Reserves

+ References

No definition available.

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- Definition

Far Value Inputs, Discount Rate, Risk Margin

+ References

No definition available.

+ Details

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

+ Details

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ 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

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Risk associated with risk of default, credit spread risk and downgrade risk, expressed as a percentage, used as an input to measure fair value.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)
-URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

+ Details

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- Definition

Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

+ Details

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- Definition

This item represents the aggregate fair value of loans held as assets that are 90 days or more past due for which the fair value option has been elected.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=6957238&loc=d3e14064-108612

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