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

Amount of realized gain on investment in debt and equity securities.

No definition available.

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

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
Period Type:	duration

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

- References

No definition available.

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

- References

No definition available.

Name:	us-gaap_AvailableforsaleSecuritiesGrossRealizedGainLossExcludingOtherThanTemporaryImpairmentsAbstract
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
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 http://asc.fasb.org/extlink&oid=124269663&loc=SL82922900-210455

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

Amount of expense (reversal of expense) for expected credit loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), from change in present value of expected cash flows.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=124258926&loc=SL82922868-210454

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 50
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=124269663&loc=SL82922897-210455

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

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 http://asc.fasb.org/extlink&oid=123581744&loc=d3e27357-111563

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

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
Balance Type:	debit
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 http://asc.fasb.org/extlink&oid=123583765&loc=SL75117546-209714

Name:	us-gaap_EquitySecuritiesFvNiRealizedGain
Namespace Prefix:	us-gaap_
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 http://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 http://asc.fasb.org/extlink&oid=123583765&loc=SL75117546-209714