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Note 15 - Accumulated Other Comprehensive Income Rollforward of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | 3 Months Ended
--- | ---
Mar. 31, 2018 | Mar. 31, 2017
Other Comprehensive Income, Net of Tax [Abstract] |  |  |
AOCI, Net of Tax, beginning balance |  | $ 23,085 |
Unrealized holding gains (losses) arising during the period |  | (60,643) | $ 7,367
Less: Reclassification adjustment for net gains (losses) included in net income (loss) |  | (3,132) | (1,631)
Unrealized foreign currency translation adjustments |  | 3 | 34
Other comprehensive income (loss), net of tax |  | (54,560) | 9,032
AOCI, Net of Tax, ending balance |  | (31,475) |
Other Comprehensive Income |  |  |
Other Comprehensive Income, before Tax [Abstract] |  |  |
AOCI before Tax, Attributable to Parent, beginning balance |  | 32,669 | (19,063)
Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax |  | (76,763) | 11,334
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax | [1] | (3,964) | (2,509)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax |  | (72,799) | 13,843
Net foreign currency translation adjustments, before tax |  | 4 | 52
Other comprehensive income, before tax |  | (72,511) | 13,895
AOCI before Tax, Attributable to Parent, ending balance |  | (39,842) | (5,168)
Other Comprehensive Income, Tax [Abstract] |  |  |
AOCI, Tax, beginning balance |  | 9,584 | (6,668)
Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax |  | (16,120) | 3,967
Less: Reclassification adjustment for net (losses) gains included in net income, tax | [1] | (832) | (878)
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax |  | (15,288) | 4,845
Net foreign currency translation adjustments, tax |  | 1 | 18
Other Comprehensive Income, Tax |  | (17,951) | 4,863
AOCI Tax, ending balance |  | (8,367) | (1,805)
Other Comprehensive Income, Net of Tax [Abstract] |  |  |
AOCI, Net of Tax, beginning balance |  | 23,085 | (12,395)
Unrealized holding gains (losses) arising during the period |  | (60,643) | 7,367
Less: Reclassification adjustment for net gains (losses) included in net income (loss) | [1] | (3,132) | (1,631)
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent |  | (57,511) | 8,998
Unrealized foreign currency translation adjustments |  | 3 | 34
Other comprehensive income (loss), net of tax |  | (54,560) | 9,032
AOCI, Net of Tax, ending balance |  | (31,475) | $ (3,363)
Accounting Standards Update 2016-01 [Member] | Other Comprehensive Income |  |  |
Other Comprehensive Income, before Tax [Abstract] |  |  |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Before Tax |  | 284 |
Other Comprehensive Income, Tax [Abstract] |  |  |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Tax |  | 60 |
Other Comprehensive Income, Net of Tax [Abstract] |  |  |
Cumulative effect of adopting the accounting standard update for financial instruments |  | 224 |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Before Tax |  | 284 |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Tax |  | 60 |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Net of Tax |  | 224 |
ASU 2018-02 [Member] | Other Comprehensive Income |  |  |
Other Comprehensive Income, before Tax [Abstract] |  |  |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Before Tax |  | 0 |
Other Comprehensive Income, Tax [Abstract] |  |  |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Tax |  | (2,724) |
Other Comprehensive Income, Net of Tax [Abstract] |  |  |
Cumulative effect of adopting the accounting standard update for financial instruments |  | 2,724 |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Before Tax |  | 0 |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Tax |  | (2,724) |
Other Comprehensive Income (Loss), 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 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://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e637-108580 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=84228862&loc=d3e681-108580 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 14A -URI http://asc.fasb.org/extlink&oid=84228862&loc=SL7669686-108580 + Details
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- Definition Amount before tax of increase (decrease) in accumulated equity from transactions and other events and circumstances from non-owner sources, attributable to parent. Excludes net income (loss), and accumulated changes in equity from transactions resulting from investments by owners (distributions to owners). + References No definition available. + Details
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