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Fair Value Measurements - Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2018 | Sep. 30, 2017 | Sep. 30, 2018 | Sep. 30, 2017
Total Investments |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance at beginning of period | $ 1,360 | $ 4,845 | $ 4,539 | $ 4,959
Transfers out of Level 3 |  |  | (3,100) |
Total realized gains (losses): |  |  |  |
Included in earnings and reported as net realized investment gains | 3,663 |  | 3,663 |
Included in earnings and reported as losses incurred, net | 0 | 0 | 0 | 0
Purchases | 0 | 0 | 0 | 0
Sales | (115) | (197) | (194) | (311)
Balance at end of period | 4,908 | 4,648 | 4,908 | 4,648
Debt Securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance at beginning of period | 192 | 577 | 271 | 691
Transfers out of Level 3 |  |  | 0 |
Total realized gains (losses): |  |  |  |
Included in earnings and reported as net realized investment gains | 0 |  | 0 |
Included in earnings and reported as losses incurred, net | 0 | 0 | 0 | 0
Purchases | 0 | 0 | 0 | 0
Sales | (115) | (197) | (194) | (311)
Balance at end of period | 77 | 380 | 77 | 380
Equity securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance at beginning of period | 1,168 | 4,268 | 4,268 | 4,268
Transfers out of Level 3 |  |  | (3,100) |
Total realized gains (losses): |  |  |  |
Included in earnings and reported as net realized investment gains | 3,663 |  | 3,663 |
Included in earnings and reported as losses incurred, net | 0 | 0 | 0 | 0
Purchases | 0 | 0 | 0 | 0
Sales | 0 | 0 | 0 | 0
Balance at end of period | 4,831 | 4,268 | 4,831 | 4,268
Real Estate Acquired |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance at beginning of period | 13,321 | 10,271 | 12,713 | 11,748
Transfers out of Level 3 |  |  | 0 |
Total realized gains (losses): |  |  |  |
Included in earnings and reported as net realized investment gains | 0 |  | 0 |
Included in earnings and reported as losses incurred, net | (450) | (592) | (1,104) | (818)
Purchases | 7,979 | 8,881 | 24,742 | 26,985
Sales | (8,511) | (6,832) | (24,012) | (26,187)
Balance at end of period | $ 12,339 | $ 11,728 | $ 12,339 | $ 11,728

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- Definition Fair Value, Measurement With Unobservable Inputs Reconciliation, Recurring Basis, Asset, Gain (Loss) Included In Earnings, Reported As Loss Incurred, Net + References No definition available. + Details
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. + References No definition available. + Details
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- Definition Amount of gain (loss) recognized in the income statement for financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(1) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount of sale of financial instrument classified as an asset measured using unobservable inputs that reflect the entity's own assumption about the assumptions market participants would use in pricing. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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- Definition Amount of transfers of financial instrument classified as an asset out of level 3 of the fair value hierarchy. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
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