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Note 15 - Accumulated Other Comprehensive Income (Loss) Rollforward of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | 3 Months Ended |
--- | --- | ---
Mar. 31, 2019 | Mar. 31, 2018 | Dec. 31, 2017
Other Comprehensive Income, Net of Tax [Abstract] |  |  |  |
AOCI, Net of Tax, Balance at beginning of period |  | $ (60,920) |  |
Unrealized holding gains (losses) arising during the period |  | 78,023 | $ (60,643) |
Less: Reclassification adjustment for net gains (losses) included in net income (loss) |  | (391) | (3,132) |
Unrealized foreign currency translation adjustments |  | 0 | 3 |
Other comprehensive income (loss), net of tax |  | 78,414 | (57,508) |
AOCI, Net of Tax, Balance at end of period |  | 17,494 |  |
Other Comprehensive Income |  |  |  |
Other Comprehensive Income, before Tax [Abstract] |  |  |  |
AOCI before Tax, Balance at beginning of period |  | (77,114) | 32,669 |
AOCI before Tax, Balance adjusted for cumulative effect of adopting accounting standard updates |  |  | 32,953 |
Unrealized holding gains (losses) arising during the period |  | 98,763 | (76,763) |
Less: Reclassification adjustment for net gains (losses) included in net income | [1] | (495) | (3,964) |
Net unrealized gains (losses) on investments |  | 99,258 | (72,799) |
Unrealized foreign currency translation adjustments |  |  | 4 |
Other comprehensive income (loss) |  | 99,258 | (72,795) |
AOCI before Tax, Balance at end of period |  | 22,144 | (39,842) |
Other Comprehensive Income, Tax [Abstract] |  |  |  |
AOCI, Tax, Balance at beginning of period |  | (16,194) | 9,584 |
AOCI, Tax, Balance adjusted for Cumulative Effect of Adopting Accounting Standard Updates |  |  | 6,920 |
Unrealized holding gains (losses) arising during the period |  | 20,740 | (16,120) |
Less: Reclassification adjustment for net gains (losses) included in net income | [1] | (104) | (832) |
Net unrealized gains (losses) on investments |  | 20,844 | (15,288) |
Unrealized foreign currency translation adjustments |  |  | 1 |
Other comprehensive income (loss) |  | 20,844 | (15,287) |
AOCI Tax, Balance at end of period |  | 4,650 | (8,367) |
Other Comprehensive Income, Net of Tax [Abstract] |  |  |  |
AOCI, Net of Tax, Balance at beginning of period |  | (60,920) | 23,085 |
AOCI, Net of Tax, Balance adjusted for Cumulative Effect of Adopting Accounting Standard Updates |  |  | 26,033 |
Unrealized holding gains (losses) arising during the period |  | 78,023 | (60,643) |
Less: Reclassification adjustment for net gains (losses) included in net income (loss) | [1] | (391) | (3,132) |
Net unrealized gains (losses) on investments |  | 78,414 | (57,511) |
Net foreign currency translation adjustments |  |  | 3 |
Other comprehensive income (loss), net of tax |  | 78,414 | (57,508) |
AOCI, Net of Tax, Balance at end of period |  | $ 17,494 | $ (31,475) |
ASU 2016-01 | Other Comprehensive Income |  |  |  |
Other Comprehensive Income, before Tax [Abstract] |  |  |  |
AOCI before tax,Cumulative Effect of Adopting an Accounting Standard Update |  |  |  | $ 284
Other Comprehensive Income, Tax [Abstract] |  |  |  |
AOCI, Tax, Cumulative Effect of Adopting an Accounting Standard Update |  |  |  | 60
Other Comprehensive Income, Net of Tax [Abstract] |  |  |  |
AOCI, Net of Tax, Cumulative Effect of Adopting an Accounting Standard Update, Net of Tax |  |  |  | 224
ASU 2018-02 | Other Comprehensive Income |  |  |  |
Other Comprehensive Income, before Tax [Abstract] |  |  |  |
AOCI before tax,Cumulative Effect of Adopting an Accounting Standard Update |  |  |  | 0
Other Comprehensive Income, Tax [Abstract] |  |  |  |
AOCI, Tax, Cumulative Effect of Adopting an Accounting Standard Update |  |  |  | (2,724)
Other Comprehensive Income, Net of Tax [Abstract] |  |  |  |
AOCI, Net of Tax, Cumulative Effect of Adopting an Accounting Standard Update, Net of Tax |  |  |  | $ 2,724
[1] | Included in net gains (losses) on investments and other financial instruments on our condensed consolidated statements of operations.

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- Definition Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=114867106&loc=SL7669686-108580 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=114867106&loc=d3e681-108580 + Details
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