Goodwill and Intangible Assets (Goodwill Rollforward) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Goodwill [Line Items]
Beginning balance	$ 261,792	$ 254,832
Ending balance	262,997	261,792
Code Plus [Member]
Goodwill [Line Items]
Goodwill acquired during period		3,402
TexPly [Member]
Goodwill [Line Items]
Goodwill acquired during period		$ 3,558
WE Shone Co [Member]
Goodwill [Line Items]
Goodwill acquired during period	2,526
Coleman Floor [Member]
Goodwill [Line Items]
Goodwill, Written off Related to Sale of Business Unit	$ (1,321)

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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