Accounts Receivable Accounts Receivable (Allowance) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018		Dec. 31, 2017	Dec. 31, 2016
Allowance for Doubtful Accounts Receivable [Roll Forward]
Balance at January 1	$ 4,771		$ 4,162	$ 2,357
Write-offs	(4,676)		(3,665)	(2,186)
Recoveries	1,460		960	2,587
Increase in allowance	4,906		3,314	1,404
Other	(1,557)	[1]	0	0
Balance at December 31	4,904		4,771	4,162
Decrease in allowance	4,906		$ 3,314	$ 1,404
Other long-term assets [Member]
Allowance for Doubtful Accounts Receivable [Roll Forward]
Notes receivable	2,600
Allowance for notes receivable	1,300
Coleman Floor [Member]
Allowance for Doubtful Accounts Receivable [Roll Forward]
Increase in allowance	300
Decrease in allowance	$ 300

[1] During the year ended December 31, 2018, the Company entered into a promissory note with one of its customers resulting in a note receivable of $2.6 million and corresponding allowance of $1.3 million, included in other long-term assets. These amounts were previously included in trade receivables and allowance for doubtful accounts, respectively, within accounts receivable. Additionally, the allowance for doubtful accounts balance declined by $0.3 million during the year ended December 31, 2018 in connection with the sale of accounts receivable in the Coleman Floor disposition. See Note 3 for further details.