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Variable Interest Entities and Noncontrolling Interests - Non-redeemable noncontrolling interests (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Sep. 30, 2020 | Sep. 30, 2019
Noncontrolling Interest [Line Items] |  |  |  |  |
Non-redeemable noncontrolling interests, beginning of period |  |  |  | $ 762,777 |
Amounts attributable to noncontrolling interests |  | $ 67,768 | $ 136 | (578) | $ 54,819
Other comprehensive (income) loss attributable to noncontrolling interests |  | 10,820 | (764) | (2,127) | 6,266
Non-redeemable noncontrolling interests, end of period |  | 757,920 | 854,924 | 757,920 | 854,924
Watford Holdings Ltd |  |  |  |  |
Noncontrolling Interest [Line Items] |  |  |  |  |
Non-redeemable noncontrolling interests, beginning of period |  | 679,089 | 855,347 | 762,777 | 791,560
Additional paid in capital attributable to noncontrolling interests |  | 243 | 205 | 715 | 2,279
Repurchases attributable to non-redeemable noncontrolling interests | [1] |  |  | (2,867) | 0
Amounts attributable to noncontrolling interests |  | 67,768 | 136 | (578) | 54,819
Other comprehensive (income) loss attributable to noncontrolling interests |  | 10,820 | (764) | (2,127) | 6,266
Non-redeemable noncontrolling interests, end of period |  | $ 757,920 | $ 854,924 | $ 757,920 | $ 854,924
Noncontrolling shareholders | Common shares | Watford Holdings Ltd |  |  |  |  |
Noncontrolling Interest [Line Items] |  |  |  |  |
Noncontrolling interest, ownership percentage by noncontrolling owners |  | 87.00% |  | 87.00% |
[1] | During 2020, Watford’s board of directors authorized the investment in Watford’s common shares through a share repurchase program.

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