Name:	axs_DebtAndEquitySecuritiesRealizedGainAbstractAbstract
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Amount of realized loss on investment in debt and equity securities.

No definition available.

Name:	axs_DebtAndEquitySecuritiesRealizedLoss
Namespace Prefix:	axs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
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- References

No definition available.

Name:	axs_DebtandEquitySecuritiesRealizedLossAbstractAbstract
Namespace Prefix:	axs_
Data Type:	xbrli:stringItemType
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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments and relating to the entity's investment portfolio.

No definition available.

Name:	axs_DerivativeInstrumentsNotDesignatedAsHedgingInstrumentsInvestmentPortfolioGainLoss
Namespace Prefix:	axs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

This item represents the net realized gains and losses on available for sale debt securities, the net realized and unrealized gains and losses on equity securities with FV recorded in net income, together with the change in fair value of investment derivatives, and expected and realized credit losses.

No definition available.

Name:	axs_NetInvestmentGainLoss
Namespace Prefix:	axs_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of writeoff of allowance for credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-Subparagraph (g)
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

Name:	us-gaap_DebtSecuritiesAvailableForSaleAllowanceForCreditLossWriteoff
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Period Type:	duration

Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 9
-URI https://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

Name:	us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease
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Data Type:	xbrli:monetaryItemType
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Amount of realized gain on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 9
-Subparagraph (a)
-URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27357-111563

Name:	us-gaap_DebtSecuritiesAvailableForSaleRealizedGain
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Amount of realized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Name:	us-gaap_DebtSecuritiesAvailableForSaleRealizedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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Period Type:	duration

Amount of realized gain from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=126980263&loc=SL75117546-209714

Name:	us-gaap_EquitySecuritiesFvNiRealizedGain
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Amount of realized loss from sale of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Name:	us-gaap_EquitySecuritiesFvNiRealizedLoss
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 220
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(d))
-URI https://asc.fasb.org/extlink&oid=120400993&loc=SL114874131-224263

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
-SubTopic 10
-Section 50
-Paragraph 4
-URI https://asc.fasb.org/extlink&oid=126980263&loc=SL75117546-209714