Represents amount of capital loss carryover available to offset future capital gains expires in 2024.

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Amount, after deferred tax asset current, of deferred tax liability current attributable to taxable differences with jurisdictional netting.

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Represents percentage of withholding income tax rate.

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Represents percentage of withholding tax on dividends.

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to statutory income tax expense (benefit) outside of the country of domicile.

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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.

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

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Other revenues from oil and gas producing activities.

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Income Taxes (Detail Textuals) - USD ($) $ in Millions	12 Months Ended
Income Taxes (Detail Textuals) - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Operating Loss Carryforwards [Line Items]
PRC income tax rate	25.00%
Withholding income tax rate	10.00%
Withholding tax on dividends rate	5.00%
Reduction in deferred tax assets due to change in tax rate		$ 4.4
Cumulative tax loss carryforwards	$ 26.8
Valuation allowance increased (decreased)	3.0
Results of operations, revenue, other	2.3
Deferred Tax Liabilities			$ 0.7
Capital loss carryover available To offset future capital gains expires in 2024	0.4
United States
Operating Loss Carryforwards [Line Items]
Cumulative tax loss carryforwards	38.9
PRC/Hong Kong
Operating Loss Carryforwards [Line Items]
Cumulative tax loss carryforwards	$ 28.3