Fair Value, Option, Fair Value Carrying Amount, Assets

No definition available.

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

- Definition

Fair Value, Option, Unpaid Principal Balance, Assets

+ References

No definition available.

+ Details

Name:	ahl_FairValueOptionUnpaidPrincipalBalanceAssets
Namespace Prefix:	ahl_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

Name:	us-gaap_FairValueOptionAggregateDifferencesLoansAndLongTermReceivables
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

+ Details

Name:	us-gaap_FairValueOptionChangesInFairValueGainLoss1
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- 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

Name:	us-gaap_FairValueOptionLoansHeldAsAssets90DaysOrMorePastDue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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

Name:	us-gaap_FairValueOptionQuantitativeDisclosuresLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_LoansReceivableMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_GainLossOnInvestmentsMember1
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=ahl_DebtSecuritiesTradingMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=us-gaap_InvestmentIncomeMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=ahl_InvestmentFundsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_IncomeStatementLocationAxis=ahl_FuturePolicyBenefitsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_FinancialInstrumentAxis=us-gaap_InsuranceContractRightsAndObligationsFairValueOptionMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

Fair Value - Fair Value Option (Details) - USD ($)	3 Months Ended		6 Months Ended
Fair Value - Fair Value Option (Details) - USD ($)	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	$ 31,000,000	$ (11,000,000)	$ 37,000,000	$ (14,000,000)
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)	1,000,000	0	1,000,000	0
Unpaid principal balance	29,000,000		29,000,000		30,000,000
Mark to fair value	3,000,000		3,000,000		2,000,000
Fair value	32,000,000		32,000,000		$ 32,000,000
Investment related gains (losses) \| Trading securities
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	78,000,000	(75,000,000)	128,000,000	(164,000,000)
Net investment income \| Investment funds
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	4,000,000	13,000,000	0	15,000,000
Future policy and other policy benefits \| Future policy benefits
Fair Value, Option, Quantitative Disclosures [Line Items]
Total gains (losses)	$ (52,000,000)	$ 51,000,000	$ (92,000,000)	$ 135,000,000