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Fair Value Measurements - Changes in Level 3 (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Asset-backed securities |  |  |
Changes in Level 3 |  |  |
Beginning balance |  |  | $ 52,941
Total gains or losses |  |  |
Included in earnings (or changes in net assets) |  |  | (28)
Included in other comprehensive income |  |  | (541)
Purchases, issuances, sales, and settlements |  |  |
Sales | $ (27,455) |  |
Transfers out of Level 3 |  |  | (24,917)
States and political subdivisions |  |  |
Changes in Level 3 |  |  |
Beginning balance |  | $ 111 | 118
Total gains or losses |  |  |
Included in other comprehensive income |  | 9 |
Purchases, issuances, sales, and settlements |  |  |
Settlements |  | (78) |
Ending balance | 118 |  | 118
Transfers out of Level 3 |  | (42) |
Mortgage servicing rights |  |  |
Changes in Level 3 |  |  |
Beginning balance |  | 5,847 | 5,462
Total gains or losses |  |  |
Included in earnings (or changes in net assets) |  | (1,394) | (668)
Purchases, issuances, sales, and settlements |  |  |
Issuances | 1,209 | 1,148 |
Settlements | (533) | (526) |
Ending balance | $ 5,470 | $ 5,075 | $ 5,470

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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 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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