Consolidated Statements Of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Operating Activities:
Net income	$ 172,492	$ 212,948	$ 455,361
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	191,108	167,512	152,138
Noncash compensation	50,054	57,927	61,929
Noncash income from financial services	(27,027)	(30,116)	(29,405)
Deferred income taxes	73,614	(26,056)	(16,343)
Excess tax benefits from share-based compensation	0	(3,578)	(34,654)
Other than Temporary Impairment Losses, Investments	25,395	0	0
Other, net	3,401	13,462	6,802
Changes in operating assets and liabilities:
Trade receivables	(17,064)	2,030	48,798
Inventories	(26,958)	111,999	(148,725)
Accounts payable	39,516	(62,693)	(46,095)
Accrued expenses	94,557	145,261	9,182
Income taxes payable/receivable	23,410	(1,997)	(247)
Prepaid expenses and other, net	(22,518)	(14,916)	(18,510)
Net cash provided by operating activities	579,980	571,783	440,231
Investing Activities:
Purchase of property and equipment	(184,388)	(209,137)	(249,485)
Investment in finance affiliate	(25,230)	(8,641)	(23,087)
Distributions from finance affiliate	57,502	43,820	42,527
Investment in other affiliates	(625)	(11,595)	(17,848)
Acquisition and disposal of businesses, net of cash acquired	1,645	(723,705)	(41,195)
Net cash used for investing activities	(151,096)	(909,258)	(289,088)
Financing Activities:
Borrowings under debt arrangements / capital lease obligations	2,186,939	3,232,137	2,631,067
Repayments under debt arrangements / capital lease obligations	(2,421,473)	(2,552,760)	(2,385,480)
Repurchase and retirement of common shares	(90,461)	(245,816)	(293,616)
Cash dividends to shareholders	(145,423)	(140,336)	(139,285)
Excess tax benefits from share-based compensation	0	3,578	34,654
Proceeds from stock issuances under employee plans	42,738	17,690	32,535
Net cash provided by (used for) financing activities	(427,680)	314,493	(120,125)
Impact of currency exchange rates on cash balances	9,816	(5,042)	(13,269)
Net increase (decrease) in cash and cash equivalents	11,020	(28,024)	17,749
Cash and cash equivalents at beginning of period	127,325	155,349	137,600
Cash and cash equivalents at end of period	138,345	127,325	155,349
Noncash Activity:
Property and equipment obtained through capital leases and notes payable	0	0	14,500
Supplemental Cash Flow Information:
Interest paid on debt borrowings	30,884	15,833	11,451
Income taxes paid	$ 46,308	$ 126,799	$ 244,328