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Fair Value Measurements - Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2020 | Dec. 31, 2019
Total fixed income securities |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance at beginning of period | $ 0 | $ 13
Total realized/unrealized gains (losses) [Abstract] |  |
Included in earnings and reported as losses incurred, net | 0 | 0
Acquisitions | 0 | 0
Sales | 0 | (13)
Balance at end of period | 0 | 0
Real Estate Acquired |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |
Balance at beginning of period | 7,252 | 14,535
Total realized/unrealized gains (losses) [Abstract] |  |
Included in earnings and reported as losses incurred, net | 660 | (476)
Acquisitions | 8,609 | 24,204
Sales | (15,429) | (31,011)
Balance at end of period | $ 1,092 | $ 7,252

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- Definition Amount of gain (loss) recognized in income from asset measured at fair value on recurring basis using unobservable input (level 3). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258 + Details
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