Impact on stockholders' equity of the effects of tax law changes during the period.

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- Definition

Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

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-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

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Amount of income tax expense (benefit) from continuing operations attributable to an adjustment of a deferred tax liability or asset for enacted changes in tax laws or rates or a change in the tax status of the entity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Note 9 - Income Taxes (Details Textual) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent			35.00%	35.00%	35.00%
Income Tax Expense (Benefit), Continuing Operations, Adjustment of Deferred Tax (Asset) Liability			$ 11,500
Stockholders' Equity, Effects of Tax Law Changes
Earliest Tax Year [Member] \| Domestic Tax Authority [Member]
Open Tax Year			2014
Earliest Tax Year [Member] \| State and Local Jurisdiction [Member]
Open Tax Year			2014
Metropolitan [Member]
Operating Loss Carryforwards	$ 35,600		$ 35,600
Retained Earnings [Member]
Stockholders' Equity, Effects of Tax Law Changes			$ 3,016
Retained Earnings [Member] \| New Accounting Pronouncement, Early Adoption, Effect [Member]
Stockholders' Equity, Effects of Tax Law Changes	$ 3,000
Scenario, Forecast [Member]
Effective Income Tax Rate Reconciliation, at Federal Statutory Income Tax Rate, Percent		21.00%