Summary of Significant Accounting Policies - Additional Information (Detail) - shares	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Schedule Of Significant Accounting Policies [Line Items]
Moving average period to determine market value of plan assets	5 years
Percentage rate of gains or losses recognizes in fair market value of assets	20.00%
Diluted	14,636,000	12,590,000
Warrants [Member]
Schedule Of Significant Accounting Policies [Line Items]
Diluted	14,636,022	12,590,230
Stock Option [Member] \| Warrants [Member]
Schedule Of Significant Accounting Policies [Line Items]
Weighted average outstanding stock options	1,809,432	671,886
Restricted Stock Units (RSUs) [Member]
Schedule Of Significant Accounting Policies [Line Items]
Vesting period, years	3 years
Stock Option [Member]
Schedule Of Significant Accounting Policies [Line Items]
Vesting period, years	3 years
Minimum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Investments in joint ventures	20.00%
Defined benefit plan actuarial gain loss percentage	10.00%
Minimum [Member] \| Land Improvements [Member]
Schedule Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	15 years
Minimum [Member] \| Buildings [Member]
Schedule Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	25 years
Minimum [Member] \| Machinery and Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	3 years
Maximum [Member]
Schedule Of Significant Accounting Policies [Line Items]
Investments in joint ventures	50.00%
Expected disposal period of assets held for sale	1 year
Defined benefit plan actuarial gain loss percentage	10.00%
Maximum [Member] \| Land Improvements [Member]
Schedule Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	20 years
Maximum [Member] \| Buildings [Member]
Schedule Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	50 years
Maximum [Member] \| Machinery and Equipment [Member]
Schedule Of Significant Accounting Policies [Line Items]
Property, plant and equipment, estimated useful life	25 years

Assets held for sale expected disposal period.

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- Definition

The threshold for defined benefit plans in determining how actuarial gains or losses are amortized/included in net periodic pension and other postretirement costs.

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- Definition

The time frame over which unrealized gains and losses are amortized in order to determine the market-related value of plan assets.

+ References

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Percentage rate of gains or losses recognizes in fair market value of assets.

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Schedule Of Significant Accounting Policies [Line Items]

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.

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- Definition

The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Useful life of long lived, physical assets used in the normal conduct of business and not intended for resale, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. Examples include, but not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

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Period over which grantee's right to exercise award under share-based payment arrangement is no longer contingent on satisfaction of service or performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Includes, but is not limited to, combination of market, performance or service condition.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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