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Note 15 - Accumulated Other Comprehensive Income Rollforward of Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017 | Mar. 31, 2018 | Dec. 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 |  | $ (27,804) | $ 20,239 | (88,447) | $ 27,606 |  |
Less: Reclassification adjustment for net gains (losses) included in net income (loss) |  | (1,336) | (1,167) | (4,468) | (2,798) |  |
Unrealized foreign currency translation adjustments |  | 0 | 74 | 3 | 108 |  |
Other comprehensive income (loss), net of tax |  | (26,468) | 21,480 | (83,976) | 30,512 |  |
AOCI, Net of Tax, ending balance |  | (57,943) |  | (57,943) |  |  |
Other Comprehensive Income |  |  |  |  |  |  |
Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |  |
AOCI before Tax, Attributable to Parent, Adjusted for Cumulative Effect of Adopting Accounting Standard Updates |  |  |  |  |  | $ (39,842) | $ 32,953
Other Comprehensive Income, before Tax [Abstract] |  |  |  |  |  |  |
AOCI before Tax, Attributable to Parent, beginning balance |  | (39,842) | (5,168) | 32,669 | (19,063) |  |
Unrealized Holding Gain (Loss) on Securities Arising During Period, before Tax |  | (35,194) | 31,137 | (111,957) | 42,471 |  |
Other Comprehensive Income (Loss), Reclassification Adjustment from AOCI for Sale of Securities, before Tax | [1] | (1,691) | (1,795) | (5,655) | (4,304) |  |
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, before Tax |  | (33,503) | 32,932 | (106,302) | 46,775 |  |
Net foreign currency translation adjustments, before tax |  | 0 | 114 | 4 | 166 |  |
Other comprehensive income, before tax |  | (33,503) | 33,046 | (106,298) | 46,941 |  |
AOCI before Tax, Attributable to Parent, ending balance |  | (73,345) | 27,878 | (73,345) | 27,878 |  |
Other Comprehensive Income, Tax [Abstract] |  |  |  |  |  |  |
AOCI, Tax, beginning balance |  | (8,367) | (1,805) | 9,584 | (6,668) |  |
Unrealized Holding Gain (Loss) on Securities Arising During Period, Tax |  | (7,390) | 10,898 | (23,510) | 14,865 |  |
Less: Reclassification adjustment for net (losses) gains included in net income, tax | [1] | (355) | (628) | (1,187) | (1,506) |  |
Other Comprehensive Income (Loss), Available-for-sale Securities, Tax |  | (7,035) | 11,526 | (22,323) | 16,371 |  |
Net foreign currency translation adjustments, tax |  | 0 | 40 | 1 | 58 |  |
Other Comprehensive Income, Tax |  | (7,035) | 11,566 | (22,322) | 16,429 |  |
AOCI Tax, ending balance |  | (15,402) | 9,761 | (15,402) | 9,761 |  |
Other Comprehensive Income, Net of Tax [Abstract] |  |  |  |  |  |  |
AOCI, Net of Tax, beginning balance |  | (31,475) | (3,363) | 23,085 | (12,395) |  |
Unrealized holding gains (losses) arising during the period |  | (27,804) | 20,239 | (88,447) | 27,606 |  |
Less: Reclassification adjustment for net gains (losses) included in net income (loss) | [1] | (1,336) | (1,167) | (4,468) | (2,798) |  |
Other Comprehensive Income (Loss), Available-for-sale Securities Adjustment, Net of Tax, Portion Attributable to Parent |  | (26,468) | 21,406 | (83,979) | 30,404 |  |
Unrealized foreign currency translation adjustments |  | 0 | 74 | 3 | 108 |  |
Other comprehensive income (loss), net of tax |  | (26,468) | 21,480 | (83,976) | 30,512 |  |
AOCI, Net of Tax, ending balance |  | $ (57,943) | $ 18,117 | $ (57,943) | $ 18,117 |  |
AOCI Tax, Attributable to Parent, Adjusted for Cumulative Effect of Adopting Accounting Standard Updates |  |  |  |  |  | (8,367) | 6,920
Accumulated Other Comprehensive Income (Loss), Net of Tax, Adjusted for Cumulative Effect of Adopting Accounting Standard Updates |  |  |  |  |  | (31,475) | 26,033
Accounting Standards Update 2016-01 [Member] | Other Comprehensive Income |  |  |  |  |  |  |
Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |  |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Before Tax |  |  |  |  |  | 0 | 284
Other Comprehensive Income, Net of Tax [Abstract] |  |  |  |  |  |  |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update |  |  |  |  |  | 0 | 60
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Net of Tax |  |  |  |  |  | 0 | 224
ASU 2018-02 [Member] | Other Comprehensive Income |  |  |  |  |  |  |
Accumulated Other Comprehensive Income [Line Items] |  |  |  |  |  |  |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Before Tax |  |  |  |  |  | 0 | 0
Other Comprehensive Income, Net of Tax [Abstract] |  |  |  |  |  |  |
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update |  |  |  |  |  | 0 | (2,724)
Other Comprehensive Income (Loss), Cumulative Effect of Adopting an Accounting Standard Update, Net of Tax |  |  |  |  |  | $ 0 | $ 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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