Accrued Expenses And Other Current Liabilities (Schedule Of Reconciliation Of The Activity Related To Accrued Warranty) (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Movement in Standard and Extended Product Warranty Accrual, Increase (Decrease) [Roll Forward]
Balance at beginning of period	$ 32,393	$ 26,204
Provision for warranty expense	18,570	15,494
Warranty liability from acquired businesses	150	125
Warranty costs paid	(13,963)	(10,833)
Balance at end of period	37,150	30,990
Less long-term portion	13,592	11,383
Current portion of accrued warranty	$ 23,558	$ 19,607	$ 20,393