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Payment terms on sales.

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Significant accounting policies.

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Tax cuts and jobs act of 2017 reclassification from AOCI to retained earnings.

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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Date the declared dividend will be paid, in CCYY-MM-DD format.

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The per share amount of a dividend declared, but not paid, as of the financial reporting date.

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Date the dividend to be paid was declared, in CCYY-MM-DD format.

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Date the holder must own the stock to be entitled to the dividend, in CCYY-MM-DD format.

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

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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Present value of lessee's discounted obligation for lease payments from operating lease.

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Amount of lessee's right to use underlying asset under operating lease.

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The amount of a reclassification adjustment made to prior period financial statement amounts.

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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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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

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Summary of Significant Accounting Policies (Narrative) (Details)			12 Months Ended
	Jan. 22, 2019 USD ($)	Jan. 01, 2018 USD ($)	Dec. 31, 2018 USD ($) customer	Dec. 31, 2017 USD ($) customer	Dec. 31, 2016 USD ($) customer	Feb. 20, 2019 $ / shares
Significant Accounting Policies [Line Items]
Gross sales			$ 975,300,000	$ 893,600,000	$ 837,300,000
Dividends payable, date declared			Feb. 20, 2019
Dividends payable, date to be paid			Mar. 20, 2019
Dividends payable, date of record			Mar. 05, 2019
Corporate statutory tax rate			21.00%	35.00%
Tax cuts and jobs act of 2017 reclassification from AOCI to retained earnings		$ 54,300,000
ASU 2017-07 [Member] \| Increase Decrease in Cost of Goods Sold [Member]
Significant Accounting Policies [Line Items]
Reclassification adjustment amount				$ 8,400,000	1,300,000
ASU 2017-07 [Member] \| Increase Decrease in Other Non-operating Income, Net [Member]
Significant Accounting Policies [Line Items]
Reclassification adjustment amount				11,400,000	7,000,000
ASU 2017-07 [Member] \| Increase Decrease in Selling General and Administrative Expenses [Member]
Significant Accounting Policies [Line Items]
Reclassification adjustment amount				$ 3,000,000	$ 5,700,000
Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Dividends declared per common share outstanding \| $ / shares						$ 0.175
Architectural Components Group, Inc. [Member] \| Subsequent Event [Member]
Significant Accounting Policies [Line Items]
Annual revenue	$ 35,000,000
Developed Technology [Member]
Significant Accounting Policies [Line Items]
Definite-lived intangible assets, useful life			15 years
Minimum [Member]
Significant Accounting Policies [Line Items]
Expect to recognize ROU asset			$ 25,000,000
Expect to recognize lease liabilities			$ 25,000,000
Minimum [Member] \| Customer Relationships [Member]
Significant Accounting Policies [Line Items]
Definite-lived intangible assets, useful life			7 years
Minimum [Member] \| Machinery And Equipment [Member]
Significant Accounting Policies [Line Items]
Useful Life			3 years
Minimum [Member] \| Computer Equipment [Member]
Significant Accounting Policies [Line Items]
Useful Life			3 years
Minimum [Member] \| Office Furniture And Equipment [Member]
Significant Accounting Policies [Line Items]
Useful Life			5 years
Minimum [Member] \| Dryer Components [Member]
Significant Accounting Policies [Line Items]
Useful Life			3 years
Minimum [Member] \| Heavy Production Equipment [Member]
Significant Accounting Policies [Line Items]
Useful Life			13 years
Minimum [Member] \| Buildings [Member]
Significant Accounting Policies [Line Items]
Useful Life			15 years
Minimum [Member] \| Computer Software [Member]
Significant Accounting Policies [Line Items]
Useful Life			3 years
Maximum [Member]
Significant Accounting Policies [Line Items]
Payment terms on sales			45 days
Incremental costs to fulfill customer arrangements amortization period			1 year
Expect to recognize ROU asset			$ 30,000,000
Expect to recognize lease liabilities			$ 30,000,000
Maximum [Member] \| Customer Relationships [Member]
Significant Accounting Policies [Line Items]
Definite-lived intangible assets, useful life			20 years
Maximum [Member] \| Machinery And Equipment [Member]
Significant Accounting Policies [Line Items]
Useful Life			15 years
Maximum [Member] \| Computer Equipment [Member]
Significant Accounting Policies [Line Items]
Useful Life			5 years
Maximum [Member] \| Office Furniture And Equipment [Member]
Significant Accounting Policies [Line Items]
Useful Life			7 years
Maximum [Member] \| Dryer Components [Member]
Significant Accounting Policies [Line Items]
Useful Life			7 years
Maximum [Member] \| Heavy Production Equipment [Member]
Significant Accounting Policies [Line Items]
Useful Life			15 years
Maximum [Member] \| Buildings [Member]
Significant Accounting Policies [Line Items]
Useful Life			30 years
Maximum [Member] \| Computer Software [Member]
Significant Accounting Policies [Line Items]
Useful Life			7 years
Gross Sales [Member] \| Concentration Risk On Three Customers [Member]
Significant Accounting Policies [Line Items]
Number of customers accounted for significant percentage of net sales \| customer			3	3	3
Gross sales			$ 459,300,000	$ 426,100,000	$ 372,900,000
Gross Sales [Member] \| Geographic Concentration Risk [Member]
Significant Accounting Policies [Line Items]
Concentration risk, percentage			10.00%	10.00%	10.00%