Pension and Employee Benefit Plans - Summary of Pension Fund General Information (Detail)	12 Months Ended
Dec. 31, 2020
Multiemployer Plans [Line Items]
EIN/Pension Number	13-2566064
Sheet Metal Workers' National Pension Fund [Member]
Multiemployer Plans [Line Items]
EIN/Pension Number	52-6112463
Plan Number	001
Pension Protection Act Zone Status	Yellow
FIF/RP Status Pending/Implemented	Implemented
Surcharge Imposed	No
Expiration of Collective Bargaining Agreement	Various
Sheet Metal Workers Local Two Two Four Pension Plan [Member]
Multiemployer Plans [Line Items]
EIN/Pension Number	31-6171353
Plan Number	001
Pension Protection Act Zone Status	Yellow
FIF/RP Status Pending/Implemented	Implemented
Surcharge Imposed	No
Expiration of Collective Bargaining Agreement	May 31, 2022
Sheet Metal Workers Local One Seven Seven Pension Fund [Member]
Multiemployer Plans [Line Items]
EIN/Pension Number	62-6093256
Plan Number	001
Pension Protection Act Zone Status	Green
FIF/RP Status Pending/Implemented	NA
Surcharge Imposed	No
Expiration of Collective Bargaining Agreement	April 30, 2023

The Tax Identification Number (TIN), also known as an Employer Identification Number (EIN), is a unique 9-digit value assigned by the IRS.

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-Publisher SEC
-Name Regulation 12B
-Number 240
-Section 12
-Subsection b-2

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- Definition

Indicates certified zone status of multiemployer pension plan determined to be individually significant. Acceptable values are "Green", "Yellow", "Orange", "Red", "Other", and "NA".

+ References

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-Publisher FASB
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Indicates whether funding improvement plan or rehabilitation plan was implemented or pending for multiemployer pension plan, determined to be individually significant. Acceptable values are "No", "Pending", "Implemented", "Other", and "NA".

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- Definition

Plan number for multiemployer pension plan determined to be individually significant, in three-digit numeric format.

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Indicates whether employer paid surcharge to multiemployer pension plan determined to be individually significant. Acceptable values are "No", "Yes" and "NA".

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Description of the significant collective-bargaining arrangements within the range of expiration dates for collective-bargaining arrangements requiring contributions to a multiemployer plan as well as other information to help investors understand the significance of the collective-bargaining agreements and when they expire. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers.

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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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