Consolidated Statements Of Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
Sales	$ 1,502,532	$ 1,364,920	$ 2,800,005	$ 2,518,702
Cost of sales	1,117,356	1,014,534	2,091,348	1,925,825
Gross profit	385,176	350,386	708,657	592,877
Operating expenses:
Selling and marketing	122,859	118,531	240,566	232,844
Research and development	68,330	60,753	133,560	112,758
General and administrative	92,874	91,063	171,567	166,577
Total operating expenses	284,063	270,347	545,693	512,179
Income from financial services	21,344	19,143	42,769	39,573
Operating income	122,457	99,182	205,733	120,271
Non-operating expense:
Interest expense	9,216	8,032	17,264	15,946
Equity in loss of other affiliates	3,954	1,336	25,465	3,236
Other expense (income), net	(3,561)	(2,152)	(23,536)	9,456
Income before income taxes	112,848	91,966	186,540	91,633
Provision for income taxes	20,308	29,925	38,286	32,503
Net income	$ 92,540	$ 62,041	$ 148,254	$ 59,130
Basic net income per share (in dollars per share)	$ 1.46	$ 0.99	$ 2.34	$ 0.94
Diluted net income per share (in dollars per share)	$ 1.43	$ 0.97	$ 2.28	$ 0.92
Weighted average shares outstanding:
Basic (in shares)	63,172	62,895	63,238	63,012
Diluted (in shares)	64,886	63,807	65,052	63,970