Financial Instruments, Owned and Pledged as Collateral, Released From Restriction

No definition available.

Name:	axs_FinancialInstrumentsOwnedandPledgedasCollateralReleasedFromRestriction
Namespace Prefix:	axs_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The minimum solvency margin amount, which is a factor of the minimum statutory capital and surplus calculation, required to be maintained, in terms of the Insurance Act 1978, amendments thereto and Related Regulations of Bermuda.

+ References

No definition available.

+ Details

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

- Definition

Statutory Accounting Practices Minimum Solvency Margin Percentage Of ECR

+ References

No definition available.

+ Details

Name:	axs_StatutoryAccountingPracticesMinimumSolvencyMarginPercentageOfECR
Namespace Prefix:	axs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The minimum solvency margin amount, which is a factor of the minimum statutory capital and surplus calculation, (expressed as a percentage of net reserve for losses and loss adjustment expenses) required to be maintained, in terms of the Insurance Act 1978, amendments thereto and Related Regulations of Bermuda.

+ References

No definition available.

+ Details

Name:	axs_StatutoryAccountingPracticesMinimumSolvencyMarginPercentageOfNetReserves
Namespace Prefix:	axs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The minimum solvency margin amount, which is a factor of the minimum statutory capital and surplus calculation, (expressed as a percentage of net written premiums) required to be maintained, in terms of the Insurance Act 1978, amendments thereto and Related Regulations of Bermuda.

+ References

No definition available.

+ Details

Name:	axs_StatutoryAccountingPracticesMinimumSolvencyMarginPercentageOfNetWrittenPremiums
Namespace Prefix:	axs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The potential limit (expressed as a percentage of prior year total statutory capital and surplus) to the dividend/distribution that may be paid, without signed affidavits from the entity's directors attesting that a dividend and/or distribution in excess of this amount would not cause the entity to fail to meet its relevant margins.

+ References

No definition available.

+ Details

Name:	axs_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendOrDistributionPaymentsPotentialLimitPercentageOfPriorYearStatutoryCapitalAndSurplus
Namespace Prefix:	axs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The number of the entity's directors required to issue signed affidavits in order to pay a dividend and/or distribution in excess of a specified percentage. The directors must attest that the dividend and/or distribution would not cause the entity to fail to meet its relevant margins.

+ References

No definition available.

+ Details

Name:	axs_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsNumberOfDirectorAffidavitsRequiredToPayGreaterAmount
Namespace Prefix:	axs_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

The potential limit (expressed as a percentage of total statutory capital and surplus) to the dividend that may be paid.

+ References

No definition available.

+ Details

Name:	axs_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsPotentialLimitPercentageOfTotalStatutoryCapitalAndSurplus
Namespace Prefix:	axs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

The amount of capital support provided to Lloyd's Syndicate 1686.

+ References

No definition available.

+ Details

Name:	axs_SyndicateCapitalSupportPercentage
Namespace Prefix:	axs_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

The fair value as of the balance sheet date of financial instruments and other positions owned by the entity and pledged to counterparties as collateral, including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 30
-Section 50
-Paragraph 1A
-Subparagraph (c)(2)
-URI http://asc.fasb.org/extlink&oid=109249958&loc=SL6224234-111729

+ Details

Name:	us-gaap_FinancialInstrumentsOwnedAndPledgedAsCollateralAtFairValue
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

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

- Definition

Amount of dividends that can be declared or paid with approval of regulatory agency.

+ References

Reference 1: 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.(e))
-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

+ Details

Name:	us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithRegulatoryApproval
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of dividends that can be declared or paid without approval of regulatory agency.

+ References

+ Details

Name:	us-gaap_StatutoryAccountingPracticesStatutoryAmountAvailableForDividendPaymentsWithoutRegulatoryApproval
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

The amount of statutory capital and surplus (stockholders' equity) as of the balance sheet date using prescribed or permitted statutory accounting practices (rather than GAAP, if different) of the state or country.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(23)(c))
-URI http://asc.fasb.org/extlink&oid=119400593&loc=d3e572229-122910

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

+ Details

Name:	us-gaap_StatutoryAccountingPracticesStatutoryCapitalAndSurplusBalance
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of statutory capital required to be maintained as of the balance sheet date under prescribed or permitted statutory accounting practices.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 505
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6486098&loc=d3e24708-158529

+ Details

Name:	us-gaap_StatutoryAccountingPracticesStatutoryCapitalAndSurplusRequired
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount of net income for the period determined using accounting principles prescribed or permitted by insurance regulators.

+ References

+ Details

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

- Details

Name:	srt_ConsolidatedEntitiesAxis=axs_AxisCorporateCapitalUKLimitedIIMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_ConsolidatedEntitiesAxis=axs_AxisCorporateCapitalUKLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=axs_AxisCorporateCapitalUKLimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CollateralAxis=us-gaap_CashMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CollateralAxis=axs_FixedMaturitiesAndShortTermInvestmentsMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	srt_CounterpartyNameAxis=axs_AxisCorporateCapitalUKIILimitedMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_CollateralAxis=us-gaap_EquitySecuritiesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=country_BM
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=country_IE
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatutoryAccountingPracticesByJurisdictionAxis=country_US
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

STATUTORY FINANCIAL INFORMATION (Details)		12 Months Ended
STATUTORY FINANCIAL INFORMATION (Details)	Jan. 01, 2019	Dec. 31, 2019 USD ($) board_member	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Statutory Financial Information [Line Items]
Statutory net income		$ 364,000,000	$ 268,000,000	$ (94,000,000)
Axis Corporate Capital UK Limited II
Statutory Financial Information [Line Items]
Capital support, percentage	30.00%	30.00%
Axis Corporate Capital UK Limited
Statutory Financial Information [Line Items]
Capital support, percentage	70.00%	70.00%
Axis Corporate Capital UK Limited \| Cash
Statutory Financial Information [Line Items]
Financial instruments, as collateral, at fair value		$ 22,000,000	8,000,000
Axis Corporate Capital UK Limited \| Fixed maturities and short-term investments
Statutory Financial Information [Line Items]
Financial instruments, as collateral, at fair value		725,000,000	715,000,000
Axis Corporate Capital UK II Limited
Statutory Financial Information [Line Items]
Financial instruments, as collateral, released from restriction		47,000,000
Axis Corporate Capital UK II Limited \| Cash
Statutory Financial Information [Line Items]
Financial instruments, as collateral, at fair value		5,000,000	16,000,000
Axis Corporate Capital UK II Limited \| Fixed maturities and short-term investments
Statutory Financial Information [Line Items]
Financial instruments, as collateral, at fair value		513,000,000	528,000,000
Axis Corporate Capital UK II Limited \| Equity securities
Statutory Financial Information [Line Items]
Financial instruments, as collateral, at fair value		49,000,000	40,000,000
Bermuda
Statutory Financial Information [Line Items]
Required statutory capital and surplus		1,502,153,000	1,470,375,000
Available statutory capital and surplus		3,288,752,000	3,513,342,000
Minimum solvency margin amount		$ 100,000,000
Minimum solvency margin percentage of net written premiums		50.00%
Minimum solvency margin percentage of net reserves		15.00%
Minimum solvency margin percentage of ECR		25.00%
Limit - prior year's total statutory capital surplus (Bermuda)		25.00%
Number of directors required to sign affidavits in order to pay dividend/distribution greater than 25% of prior year statutory capital and surplus \| board_member		2
Maximum dividend/distribution payable without regulatory approval		$ 844,000,000	864,000,000
Ireland
Statutory Financial Information [Line Items]
Required statutory capital and surplus		719,405,000	637,226,000
Available statutory capital and surplus		1,069,621,000	896,868,000
Maximum dividend/distribution payable with regulatory approval		70,000,000	37,000,000
U.S.
Statutory Financial Information [Line Items]
Required statutory capital and surplus		500,750,000	489,560,000
Available statutory capital and surplus		1,713,013,000	1,668,847,000
Maximum dividend/distribution payable without regulatory approval		$ 141,000,000	$ 130,000,000
Maximum dividend limit - percentage of total statutory capital and surplus		10.00%