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Summary of Significant Accounting Policies (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Jan. 01, 2019	Jan. 01, 2018	Jan. 01, 2017
Sale Leaseback Transaction [Line Items]
Advertising costs	$ 5,900	$ 5,200	$ 4,900
Retained earnings	$ 405,668	$ 338,995
Cumulative effect of new accounting principle in period of adoption				$ 1,582	$ 274	$ 0
Minimum \| Land, Buildings and Improvements
Sale Leaseback Transaction [Line Items]
Estimated useful lives	15 years
Minimum \| Machinery and Equipment
Sale Leaseback Transaction [Line Items]
Estimated useful lives	3 years
Maximum \| Land, Buildings and Improvements
Sale Leaseback Transaction [Line Items]
Estimated useful lives	40 years
Maximum \| Machinery and Equipment
Sale Leaseback Transaction [Line Items]
Estimated useful lives	20 years
Residential Products \| Home Improvement Retail Company \| Accounts Receivable
Sale Leaseback Transaction [Line Items]
Concentrations of credit risk	13.00%	14.00%
Residential Products \| Home Improvement Retail Company \| Net sales
Sale Leaseback Transaction [Line Items]
Concentrations of credit risk	12.00%	12.00%	12.00%
Accounting Standards Update 2014-09
Sale Leaseback Transaction [Line Items]
Retained earnings					274
Retained Earnings
Sale Leaseback Transaction [Line Items]
Cumulative effect of new accounting principle in period of adoption				1,582	$ 624	$ 254
Retained Earnings \| Accounting Standards Update 2016-02
Sale Leaseback Transaction [Line Items]
Cumulative effect of new accounting principle in period of adoption				$ 1,600