XML 78 R68.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Capital Structure - Summary of Authorized and Issued Share Capital (Details) - USD ($) $ / shares in Units, $ in Thousands | Sep. 30, 2017 | Dec. 31, 2016 | Sep. 20, 2016
--- | --- | --- | ---
Class of Stock [Line Items] |  |  |
Ordinary shares, par value (in usd per share) | $ 0.0015144558 | $ 0.0015144558 |
Authorized share capital: |  |  |
Number of ordinary shares (in shares) | 969,629,030 | 969,629,030 |
Number of non-voting shares (in shares) | 6,787,880 | 6,787,880 |
Number of preference shares (in shares) | 100,000,000 | 100,000,000 |
Ordinary Shares 0.15144558¢ per share | $ 1,469 | $ 1,469 |
Non-Voting Shares 0.15144558¢ per share | 10 | 10 |
Preference Shares 0.15144558¢ per share | 152 | 152 |
Total authorized share capital | $ 1,631 | $ 1,631 |
Issued share capital: |  |  |
Number of issued ordinary shares (in shares) | 59,407,323 | 59,774,464 |
Issued ordinary shares of 0.15144558¢ per share | $ 90 | $ 91 |
Total issued share capital | $ 122 | $ 140 |
Non Voting Shares Par Or Stated Value Per Share | $ 0.0015144558 | $ 0.0015144558 |
Preference shares, par value (in usd per share) | 0.0015144558 | 0.0015144558 |
Preferred shares, liquidation preference (in USD per share) | $ 25 | $ 25 |
7.401% preference shares |  |  |
Issued share capital: |  |  |
Preference shares, issued (in shares) | 0 | 5,327,500 |
Issued preference shares of 0.15144558¢ each with a liquidation preference | $ 0 | $ 8 |
Preference shares, par value (in usd per share) |  | $ 0.0015144558 |
Preferred shares, liquidation preference (in USD per share) |  | $ 25 |
Preferred Stock Dividends Rate Percentage |  | 7.401% |
7.250% preference shares |  |  |
Issued share capital: |  |  |
Preference shares, issued (in shares) | 0 | 6,400,000 |
Issued preference shares of 0.15144558¢ each with a liquidation preference | $ 0 | $ 10 |
Preference shares, par value (in usd per share) |  | $ 0.0015144558 |
Preferred shares, liquidation preference (in USD per share) |  | $ 25 |
Preferred Stock Dividends Rate Percentage |  | 7.25% |
5.95% preference shares |  |  |
Issued share capital: |  |  |
Preference shares, issued (in shares) | 11,000,000 | 11,000,000 |
Issued preference shares of 0.15144558¢ each with a liquidation preference | $ 17 | $ 17 |
Preference shares, par value (in usd per share) | $ 0.0015144558 | $ 0.0015144558 |
Preferred shares, liquidation preference (in USD per share) | $ 25 | $ 25 |
Preferred Stock Dividends Rate Percentage | 5.95% | 5.95% |
5.625% preference shares |  |  |
Issued share capital: |  |  |
Preference shares, issued (in shares) | 10,000,000 | 10,000,000 | 10,000,000
Issued preference shares of 0.15144558¢ each with a liquidation preference | $ 15 | $ 15 |
Preference shares, par value (in usd per share) | $ 0.0015144558 | $ 0.0015144558 |
Preferred shares, liquidation preference (in USD per share) | $ 25 | $ 25 | $ 25
Preferred Stock Dividends Rate Percentage | 5.625% | 5.625% |

X
- Definition Authorized Share Capital + References No definition available. + Details
Name: | ahl_AuthorizedShareCapital
Namespace Prefix: | ahl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Authorized share capital. + References No definition available. + Details
Name: | ahl_AuthorizedShareCapitalAbstract
Namespace Prefix: | ahl_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Common stock value authorized. + References No definition available. + Details
Name: | ahl_CommonStockValueAuthorized
Namespace Prefix: | ahl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Issued share capital. + References No definition available. + Details
Name: | ahl_IssuedShareCapital
Namespace Prefix: | ahl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Issued share capital. + References No definition available. + Details
Name: | ahl_IssuedShareCapitalAbstract
Namespace Prefix: | ahl_
Data Type: | xbrli:stringItemType
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 Non voting stock shares authorized. + References No definition available. + Details
Name: | ahl_NonVotingStockSharesAuthorized
Namespace Prefix: | ahl_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Non Voting Stock Value Authorized1 + References No definition available. + Details
Name: | ahl_NonVotingStockValueAuthorized1
Namespace Prefix: | ahl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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 Preferred stock shares authorized. + References No definition available. + Details
Name: | ahl_PreferredStockValueAuthorized
Namespace Prefix: | ahl_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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://www.xbrl.org/2003/role/presentationRef -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 maximum number of common shares permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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_CommonStockSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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_CommonStockSharesIssued
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Monetary value of common stock allocated to investors to buy shares of a new issue of common stock before they are offered to the public. When stock is sold on a subscription basis, the issuer does not initially receive the total proceeds. In general, the issuer does not issue the shares to the investor until it receives the entire proceeds. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=65888546&loc=d3e21300-112643 + Details
Name: | us-gaap_CommonStockSharesSubscriptions
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21475-112644 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=84159872&loc=d3e21484-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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://www.xbrl.org/2003/role/presentationRef -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 + 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://www.xbrl.org/2003/role/presentationRef -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
- Definition The maximum number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) permitted to be issued by an entity's charter and bylaws. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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_PreferredStockSharesAuthorized
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Total number of nonredeemable preferred shares (or preferred stock redeemable solely at the option of the issuer) issued to shareholders (includes related preferred shares that were issued, repurchased, and remain in the treasury). May be all or portion of the number of preferred shares authorized. Excludes preferred shares that are classified as debt. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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_PreferredStockSharesIssued
Namespace Prefix: | us-gaap_
Data Type: | xbrli:sharesItemType
Balance Type: | na
Period Type: | instant

X
- Definition Amount of subscription received from investors who have been allocated nonredeemable preferred stock or preferred stock redeemable solely at the option of the issuer. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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_PreferredStockSharesSubscribedButUnissuedValue
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesBPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_StatementClassOfStockAxis=us-gaap_SeriesCPreferredStockMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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: |