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Investment Information - Restricted assets (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Restricted Assets [Line Items]
Restricted assets	$ 9,725,335	$ 8,733,309
Collateral or guarantees - affiliated transactions
Restricted Assets [Line Items]
Restricted assets	5,041,190	4,643,334
Collateral or guarantees - third party agreements
Restricted Assets [Line Items]
Restricted assets	3,441,929	3,083,324
Deposits with US regulatory authorities
Restricted Assets [Line Items]
Restricted assets	814,084	827,552
Deposits with non-US regulatory authorities
Restricted Assets [Line Items]
Restricted assets	428,132	179,099
Watford Holdings Ltd
Restricted Assets [Line Items]
Assets pledged as collateral	$ 1,100,000	$ 954,600

X

- Definition

Assets, consisting primarily of fixed maturities, that the Company is required to maintain with various regulatory authorities to support its insurance and reinsurance operations. The Company's insurance and reinsurance subsidiaries maintain assets in trust accounts as collateral for insurance and reinsurance transactions with affiliated companies and also have investments in segregated portfolios primarily to provide collateral or guarantees for letters of credit to third parties.

+ References

No definition available.

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- Definition

-- None. No documentation exists for this element. --

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- Definition

Total assets that cannot be used for operating purposes because of contract or regulatory requirements that are in effect for a period that extends beyond one year.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 210
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=120413173&loc=SL6242262-115580

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 954
-SubTopic 210
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=120413209&loc=SL6242269-115581

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.17)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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