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Face (par) amount of debt instrument at time of issuance.

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Contractual interest rate for funds borrowed, under the debt agreement.

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Balance held at close of period in number of shares.

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The equity interest of noncontrolling shareholders, partners or other equity holders in consolidated entity.

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No definition available.

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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.

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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.

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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.

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The cash outflow associated with the acquisition of a controlling interest in another entity or an entity that is related to it but not strictly controlled (for example, an unconsolidated subsidiary, affiliate, joint venture or equity method investment).

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Percentage of subsidiary's or equity investee's stock owned by parent company after stock transaction.

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No definition available.

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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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No definition available.

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Percentage of the Variable Interest Entity's (VIE) voting interest owned by (or beneficial interest in) the reporting entity (directly or indirectly).

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Variable Interest Entities and Noncontrolling Interests - Variable interest entity (Details) - USD ($) $ / shares in Units, $ in Thousands	1 Months Ended	3 Months Ended
	Mar. 31, 2014	Mar. 31, 2021	Dec. 31, 2020	Mar. 31, 2020
Variable Interest Entity [Line Items]
Net cash provided by (used for) operating activities		$ 762,845		$ 610,454
Net cash provided by (used for) investing activities		(493,189)		(278,496)
Net cash (used for) provided by financing activities		$ (186,602)		(134,496)
Watford Holdings Ltd
Variable Interest Entity [Line Items]
Business acquisition, share price (per share)			$ 35.00
Variable Interest Entity, Primary Beneficiary \| Watford Holdings Ltd
Variable Interest Entity [Line Items]
Initial investment contribution amount	$ 100,000
Number of shares acquired	2,500,000
Ownership percentage	11.00%	10.30%
Senior notes, face amount		$ 35,000
Senior notes, stated percentage		6.50%
Net cash provided by (used for) operating activities		$ 7,000		24,600
Net cash provided by (used for) investing activities		21,400		(35,700)
Net cash (used for) provided by financing activities		$ (1,000)		$ 12,300
Variable Interest Entity, Primary Beneficiary \| Watford Holdings Ltd \| Watford Merger Transaction
Variable Interest Entity [Line Items]
Percentage ownership after merger transaction			40.00%
Variable Interest Entity, Primary Beneficiary \| Watford Holdings Ltd \| Kelso And Company
Variable Interest Entity [Line Items]
Noncontrolling interest, ownership percentage by noncontrolling owners			30.00%
Variable Interest Entity, Primary Beneficiary \| Watford Holdings Ltd \| Warburg Pincus LLC
Variable Interest Entity [Line Items]
Noncontrolling interest, ownership percentage by noncontrolling owners			30.00%
Variable Interest Entity, Primary Beneficiary \| Watford Holdings Ltd \| Non-cumulative preferred shares
Variable Interest Entity [Line Items]
Ownership percentage		6.60%