Summary of Significant Accounting Policies (Changes In Warranty And Safety Recall Liability) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Movement in Standard Product Warranty Accrual [Roll Forward]
Balance, beginning of period	$ 94,200	$ 79,482	$ 74,217
Warranties issued during the period	53,367	57,834	60,215
Settlements made during the period	(79,300)	(82,554)	(99,298)
Recalls and changes to pre-existing warranty liabilities	63,473	39,438	44,348
Balance, end of period	$ 131,740	$ 94,200	$ 79,482