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Fair Value Measurements - Unobservable Input Reconciliation (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2017 | Jun. 30, 2016 | Jun. 30, 2017 | Jun. 30, 2016
Total Investments |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance at beginning of period | $ 4,951 | $ 4,613 | $ 4,959 | $ 4,083
Total realized/unrealized gains (losses): |  |  |  |
Included in other comprehensive income |  | 3,519 |  | 3,519
Included in earnings and reported as losses incurred, net | 0 | 0 | 0 | 0
Purchases | 0 | 0 | 0 | 3,091
Sales | (106) | (136) | (114) | (2,697)
Balance at end of period | 4,845 | 7,996 | 4,845 | 7,996
Debt Securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance at beginning of period | 683 | 1,192 | 691 | 1,228
Total realized/unrealized gains (losses): |  |  |  |
Included in other comprehensive income |  | 0 |  | 0
Included in earnings and reported as losses incurred, net | 0 | 0 | 0 | 0
Purchases | 0 | 0 | 0 | 0
Sales | (106) | (136) | (114) | (172)
Balance at end of period | 577 | 1,056 | 577 | 1,056
Equity securities |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance at beginning of period | 4,268 | 3,421 | 4,268 | 2,855
Total realized/unrealized gains (losses): |  |  |  |
Included in other comprehensive income |  | 3,519 |  | 3,519
Included in earnings and reported as losses incurred, net | 0 | 0 | 0 | 0
Purchases | 0 | 0 | 0 | 3,091
Sales | 0 | 0 | 0 | (2,525)
Balance at end of period | 4,268 | 6,940 | 4,268 | 6,940
Real Estate Acquired |  |  |  |
Fair Value, Assets Measured on Recurring Basis, Unobservable Input Reconciliation, Calculation [Roll Forward] |  |  |  |
Balance at beginning of period | 10,730 | 12,849 | 11,748 | 12,149
Total realized/unrealized gains (losses): |  |  |  |
Included in other comprehensive income |  | 0 |  | 0
Included in earnings and reported as losses incurred, net | (63) | 651 | (226) | 358
Purchases | 9,421 | 6,748 | 18,104 | 19,015
Sales | (9,817) | (10,606) | (19,355) | (21,880)
Balance at end of period | $ 10,271 | $ 9,642 | $ 10,271 | $ 9,642

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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 other comprehensive income (loss) 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)(1a) -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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