Accrued Expenses And Other Current Liabilities (Schedule of Accrued Expenses and Other Current Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Payables and Accruals [Abstract]
Employee compensation and benefits	$ 39,365	$ 47,459
Current portion of accrued warranty	23,055	20,393	$ 17,020
Customer rebates	11,124	9,329
Other	29,305	21,554
Accrued expenses and other current liabilities	$ 102,849	$ 98,735