Name:	axs_DebtAndEquitySecuritiesRealizedGainAbstractAbstract
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Amount of realized loss on investments, including debt and equity securities and mortgage loans held for investment.

No definition available.

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- References

No definition available.

Name:	axs_DebtandEquitySecuritiesRealizedLossAbstractAbstract
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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
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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
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

Name:	us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterestAllowanceForCreditLossPeriodIncreaseDecrease
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Amount, excluding accrued interest, of decrease in 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) from writeoff.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (g)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-9

Name:	us-gaap_DebtSecuritiesAvailableForSaleExcludingAccruedInterestAllowanceForCreditLossWriteoff
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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
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 9
-Subparagraph (a)
-Publisher FASB
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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_
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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4A
-Subparagraph (b)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-4A

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 825
-SubTopic 10
-Name Accounting Standards Codification
-Section 55
-Paragraph 10
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482881/825-10-55-10

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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
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-4

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
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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).

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Namespace Prefix:	us-gaap_
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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
-Topic 944
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-04(3)(d)(2))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477250/944-220-S99-1

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 321
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479536/321-10-50-4

Name:	us-gaap_EquitySecuritiesFvNiUnrealizedGainLoss
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
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Amount, excluding accrued interest, of increase (decrease) in allowance for credit loss on financing receivable. Excludes net investment in lease.

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 326
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 13
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479319/326-20-50-13

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The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 28
-Subparagraph (b)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-28

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 1
-SubTopic 310
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477409/944-310-45-1

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 2
-SubTopic 310
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477409/944-310-45-2

Reference 4: http://www.xbrl.org/2003/role/disclosureRef
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-SubTopic 310
-Topic 944
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147477363/944-310-50-1