Commitments and Contingencies Warranty Expense (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Commitments and Contingencies Disclosure [Abstract]
Total warranty expense	$ 5,991	$ 1,528	$ 13,957	$ 12,291