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Variable Interest Entity and Noncontrolling Interests - Cash flows of variable interest entity (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Net Cash Provided by (Used in) Operating Activities	$ 2,886,505	$ 2,048,459	$ 1,559,322
Net cash provided by (used for) investing activities	(3,043,226)	(1,806,483)	(554,020)
Net Cash Provided by (Used in) Financing Activities	521,278	(80,662)	(988,810)
Watford Holdings Ltd | Variable Interest Entity, Primary Beneficiary
Variable Interest Entity [Line Items]
Net Cash Provided by (Used in) Operating Activities	181,736	239,284	229,315
Net cash provided by (used for) investing activities	258,589	(140,620)	(285,281)
Net Cash Provided by (Used in) Financing Activities	$ (335,776)	$ (61,433)	$ (2,406)

X

- Definition

Amount of cash inflow (outflow) from financing activities, including discontinued operations. Financing activity cash flows include obtaining resources from owners and providing them with a return on, and a return of, their investment; borrowing money and repaying amounts borrowed, or settling the obligation; and obtaining and paying for other resources obtained from creditors on long-term credit.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3521-108585

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Amount of cash inflow (outflow) from investing activities, including discontinued operations. Investing activity cash flows include making and collecting loans and acquiring and disposing of debt or equity instruments and property, plant, and equipment and other productive assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 24
-URI http://asc.fasb.org/extlink&oid=121586364&loc=d3e3521-108585

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Amount of cash inflow (outflow) from operating activities, including discontinued operations. Operating activity cash flows include transactions, adjustments, and changes in value not defined as investing or financing activities.

+ References

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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.

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