Income Taxes - Additional Information (Detail) - USD ($)	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Schedule Of Income Taxes [Line Items]
Tax credit carryforwards	$ 300,000
Net operating loss carryforward	0
Capital loss carryforwards	$ 0
Federal statutory tax rate	21.00%	35.00%
Income Tax benefit, new tax reform	$ (11,500,000)
Percentage of carryforward NOL limitation, new tax reform	80.00%

Capital Loss Carryforwards

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- Definition

Schedule Of Income Taxes [Line Items]

+ References

No definition available.

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- Definition

Tax Cuts and Jobs Act of 2017, incomplete accounting, provisional income tax expense (benefit).

+ References

No definition available.

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- Definition

The percentage of taxable income eligible for the net operating loss deduction under the Tax Cuts and Jobs Act of 2017.

+ References

No definition available.

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- Definition

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

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
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- Definition

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

+ References

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-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 10
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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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