Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

+ References

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Amount of unrealized gain (loss) on investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI).

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 321
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-Section 50
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Present value of lessee's discounted obligation for lease payments from operating lease.

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
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Note 3 - Recent Accounting Pronouncements (Details Textual) - USD ($)		3 Months Ended	9 Months Ended
	Jan. 01, 2018	Sep. 30, 2018	Sep. 30, 2018	Sep. 30, 2017
Equity Securities, FV-NI, Unrealized Gain (Loss), Total		$ 391,000	$ (4,580,000)
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings Tax Effect	$ 515,000
Accounting Standards Update 2016-01 [Member] \| Retained Earnings [Member]
Cumulative Effect of New Accounting Principle in Period of Adoption	8,600,000
Accounting Standards Update 2016-02 [Member] \| Minimum [Member] \| Scenario, Forecast [Member]
Operating Lease, Liability, Total	30,000,000
Accounting Standards Update 2016-02 [Member] \| Maximum [Member] \| Scenario, Forecast [Member]
Operating Lease, Liability, Total	$ 40,000,000