XML 128 R96.htm IDEA: XBRL DOCUMENT v3.20.1

Capital Structure - Summary of Authorized and Issued Share Capital (Phantom) (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2019	Aug. 13, 2019	Dec. 31, 2016	May 02, 2013
Class of Stock [Line Items]
Ordinary shares, par value	$ 0.0015144558	$ 0.01
Non-voting shares, par value	0.0015144558
Preference shares, par value	0.0015144558	0.0015144558
Redemption price per share	25	25
5.950% Preference Shares (AHL PRC)
Class of Stock [Line Items]
Preference shares, par value	0.0015144558	0.0015144558
Redemption price per share	$ 25	$ 25			$ 25
Preference shares, rate	5.95%	5.95%
5.625% Preference Shares (AHL PRD)
Class of Stock [Line Items]
Preference shares, par value	$ 0.0015144558	$ 0.0015144558
Redemption price per share	$ 25	$ 25		$ 25
Preference shares, rate	5.625%	5.625%
5.625% Preference Shares, rep by Dep Shares (AHL PRE)
Class of Stock [Line Items]
Preference shares, par value	$ 0	$ 0.0015144558
Redemption price per share	$ 0	$ 25	$ 25
Preference shares, rate	0.00%	5.625%
Depositary share interest of 1/1000th in each 5.625%	0.00%

X

- Definition

Preferred Stock, Dividend Rate, Depositary Share Fractional Interest (1/1000th of 5.625% Preference Share)

+ References

No definition available.

+ Details

Name:	ahl_DepositaryShareDividendRateFractionalInterest
Namespace Prefix:	ahl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Non voting shares par or stated value per share.

+ References

No definition available.

+ Details

Name:	ahl_NonVotingSharesParOrStatedValuePerShare
Namespace Prefix:	ahl_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Preferred Stock Dividends Rate Percentage

+ References

No definition available.

+ Details

Name:	ahl_PreferredStockDividendsRatePercentage
Namespace Prefix:	ahl_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

X

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

X

- Definition

Face amount or stated value per share of common stock.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_CommonStockParOrStatedValuePerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Definition

The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08.(d)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 235
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-08(d)(1))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21484-112644

+ Details

Name:	us-gaap_PreferredStockLiquidationPreference
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Definition

Face amount or stated value per share of preferred stock nonredeemable or redeemable solely at the option of the issuer.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

Name:	us-gaap_PreferredStockParOrStatedValuePerShare
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	instant

X

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_SeriesDPreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_SeriesEPreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

X

- Details

Name:	us-gaap_StatementClassOfStockAxis=us-gaap_SeriesFPreferredStockMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: