Long-Term Debt - Term Loan Facility due April 2028 and Cash Flow Revolver (Narrative) (Details)	1 Months Ended
Apr. 30, 2018 USD ($)
Term Loan Facility
Debt Instrument [Line Items]
Discount rate (as a percent)	0.50%
Quarterly amortization installment percentage factor	1.00%
Mandatory prepayment, percentage of annual excess cash flow	50.00%
Covenant compliance, excess cash flow, minimum	$ 10,000,000
Term Loan Facility \| Minimum \| Leverage Ratio Target Achieve
Debt Instrument [Line Items]
Mandatory prepayment, percentage of annual excess cash flow	25.00%
Term Loan Facility \| Maximum \| Leverage Ratio Target Achieve
Debt Instrument [Line Items]
Mandatory prepayment, percentage of annual excess cash flow	0.00%
Term Loan Facility \| Secured Overnight Financing Rate
Debt Instrument [Line Items]
Credit spread adjustment	0.10%
Spread on variable rate, floor	0.50%
Basis spread on variable rate	3.25%
Term Loan Facility \| Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	2.25%
Term Loan Facility \| Ply Gem
Debt Instrument [Line Items]
Aggregate principal amount	$ 2,600,000,000
Cash Flow Revolver \| Minimum \| Commitment Fee Percentage One
Debt Instrument [Line Items]
Unused commitment fee, as a percent	0.25%
Cash Flow Revolver \| Maximum \| Commitment Fee Percentage One
Debt Instrument [Line Items]
Unused commitment fee, as a percent	0.50%
Cash Flow Revolver \| Secured Overnight Financing Rate
Debt Instrument [Line Items]
Credit spread adjustment	0.10%
Spread on variable rate, floor	0.00%
Cash Flow Revolver \| Secured Overnight Financing Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.50%
Cash Flow Revolver \| Secured Overnight Financing Rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%
Cash Flow Revolver \| Base Rate \| Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	1.50%
Cash Flow Revolver \| Base Rate \| Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	2.00%
Cash Flow Revolver \| Ply Gem
Debt Instrument [Line Items]
Available credit facility amount	$ 115,000,000

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Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

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