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Variable Interest Entities and Noncontrolling Interests - Redeemable noncontrolling interests (Details) - USD ($) $ / shares in Units, $ in Thousands |  | 3 Months Ended | 9 Months Ended |  |
--- | --- | --- | --- | --- | ---
Aug. 01, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019 | Jul. 31, 2019 | Mar. 31, 2014
Redeemable Noncontrolling Interest [Line Items] |  |  |  |  |  |  |
Redeemable noncontrolling interests, beginning of period |  |  |  | $ 55,404 |  |  |
Redeemable noncontrolling interests, end of period |  | $ 57,835 |  | 57,835 |  |  |
Watford Holdings Ltd |  |  |  |  |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |  |  |  |  |
Redeemable noncontrolling interests, beginning of period |  | 55,986 | $ 206,475 | 55,404 | $ 206,292 |  |
Redemption of noncontrolling interests |  | 0 | (157,709) | 0 | (157,709) |  |
Accretion of preference share issuance costs |  | 23 | 23 | 70 | 206 |  |
Other |  | 1,826 | 0 | 2,361 | 0 |  |
Redeemable noncontrolling interests, end of period |  | 57,835 | $ 48,789 | 57,835 | $ 48,789 |  |
Cumulative redeemable preference shares | Watford Holdings Ltd |  |  |  |  |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |  |  |  |  |
Par value per share |  |  |  |  |  |  | $ 0.01
Liquidation preference per share |  |  |  |  |  |  | 25.00
Issue price per share |  |  |  |  |  |  | $ 24.50
Variable Interest Entity, Primary Beneficiary | Watford Holdings Ltd |  |  |  |  |  |  |
Redeemable Noncontrolling Interest [Line Items] |  |  |  |  |  |  |
Preference shares, number of shares issued |  |  |  |  |  | 9,065,200 |
Number of preference shares redeemed | 6,919,998 |  |  |  |  |  |
Preferred shares, redemption price | $ 25.19748 |  |  |  |  |  |
Preference shares redeemed | $ 11,500 |  |  |  |  |  |
Redeemable noncontrolling interests, beginning of period |  |  |  | 52,305 |  |  |
Redeemable noncontrolling interests, end of period |  | $ 52,375 |  | $ 52,375 |  |  |

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- Definition Proceeds from Redemption Of Preferred Shares By Variable Interest Entity + References No definition available. + Details
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- Definition Decrease in redeemable noncontrolling interest (for example, but not limited to, redeeming or purchasing the interests of noncontrolling shareholders, issuance of shares (interests) by the non-wholly owned subsidiary to the parent entity for other than cash, and a buyback of shares (interest) by the non-wholly owned subsidiary from the noncontrolling interests). + References No definition available. + Details
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- Definition The per share liquidation preference (or restrictions) of nonredeemable preferred stock (or preferred stock redeemable solely at the option of the issuer) that has a preference in involuntary liquidation considerably in excess of the par or stated value of the shares. The liquidation preference is the difference between the preference in liquidation and the par or stated values of the share. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 235 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.4-08(d)) -URI http://asc.fasb.org/extlink&oid=120395691&loc=d3e23780-122690 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 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(28)) -URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21484-112644 + Details
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- Definition The price per share at which the preferred stock of an entity that has priority over common stock in the distribution of dividends and in the event of liquidation of the entity is redeemed or may be called at. The redemption features of this preferred stock are solely within the control of the issuer. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21488-112644 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21475-112644 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=109259400&loc=d3e21564-112644 + Details
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- Definition As of the reporting date, the carrying amount of noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. The noncontrolling interest holder's ownership (or holders' ownership) may be in the form of preferred shares (regardless of class), preferred partnership units (regardless of class), preferential membership interests, or any other form of preferred equity regardless of investee entity legal form. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section S99 -Paragraph 3A -Subparagraph 14 -URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section S99 -Paragraph 3A -Subparagraph (12)(c) -URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section S99 -Paragraph 3A -Subparagraph 15 -URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 480 -SubTopic 10 -Section S99 -Paragraph 3A -Subparagraph (16)(c) -URI http://asc.fasb.org/extlink&oid=65877616&loc=SL6540498-122764 + Details
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