Fair Value, Option, Fair Value Carrying Amount, Assets

No definition available.

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Namespace Prefix:	ahl_
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- Definition

Fair Value, Option, Unpaid Principal Balance, Assets

+ References

No definition available.

+ Details

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Namespace Prefix:	ahl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- 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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258

+ Details

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Period Type:	instant

- Definition

This item represents the difference between the aggregate fair value and the aggregate unpaid principal balance of loans and long-term receivables (other than securities categorized as trading, available-for-sale or held-to-maturity) that have contractual principal amounts and for which the fair value option has been elected.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

+ Details

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Period Type:	instant

- Definition

For each line item in the statement of financial position, the amounts of gains and losses from fair value changes included in earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 30
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14172-108612

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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://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 28
-Subparagraph (e)(1)
-URI http://asc.fasb.org/extlink&oid=75031198&loc=d3e14064-108612

+ Details

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Period Type:	instant

- 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.

+ Details

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Fair Value - Fair Value Option (Details) - USD ($)	3 Months Ended		9 Months Ended
Fair Value - Fair Value Option (Details) - USD ($)	Sep. 30, 2018	Sep. 30, 2017	Sep. 30, 2018	Sep. 30, 2017	Dec. 31, 2017
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	$ (18,000,000)	$ 7,000,000	$ (42,000,000)	$ 33,000,000
Assets, Level 1 to Level 2 transfers	0		0		$ 0
Mortgage loans
Fair Value, Option, Quantitative Disclosures [Line Items]
Fair value option, loans, 90 days or more past due	0		0		0
Total gains (losses)	0	(1,000,000)	0	(1,000,000)
Unpaid principal balance	36,000,000		36,000,000		40,000,000
Mark to fair value	1,000,000		1,000,000		1,000,000
Fair value	37,000,000		37,000,000		$ 41,000,000
Investment related gains (losses) \| Trading securities
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	(43,000,000)	(2,000,000)	(208,000,000)	25,000,000
Net investment income \| Investment funds
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	4,000,000	5,000,000	10,000,000	19,000,000
Future policy and other policy benefits \| Future policy benefits
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	$ 21,000,000	$ 5,000,000	$ 156,000,000	$ (10,000,000)