Supplemental Guarantor Information (Statement Of Cash Flows) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Net cash provided by (used in) operating activities	$ 68,270	$ (337,590)	$ 307,881
Cash flows from investing activities:
Capital expenditures	(39,295)	(45,440)	(48,790)
Investment in unconsolidated subsidiaries	(14,539)	(454)	(9)
Cash used for business acquisition	(430,458)	0	(82,419)
Other investing activities, net	13,100	11,330	8,605
Net cash used in investing activities	(471,192)	(34,564)	(122,613)
Cash flows from financing activities:
Financial Services borrowings	63,744	127,636	34,577
Proceeds from debt issuance	1,995,937	498,087	0
Repayments of debt	(986,919)	(239,193)	(250,631)
Borrowings under revolving credit facility	619,000	125,000	0
Repayments under revolving credit facility	(619,000)	(125,000)	0
Stock option exercises	5,845	10,535	15,627
Share repurchases	(603,206)	(442,738)	(253,019)
Dividends paid	(124,666)	(115,958)	(75,646)
Intercompany activities, net	0	0	0
Net cash provided by (used in) financing activities	350,735	(161,631)	(529,092)
Net increase (decrease)	(52,187)	(533,785)	(343,824)
Cash, cash equivalents, and restricted cash at beginning of period	775,435	1,309,220	1,653,044
Cash, cash equivalents, and restricted cash at end of period	723,248	775,435	1,309,220
Parent Company [Member]
Net cash provided by (used in) operating activities	256,722	185,946	206,485
Cash flows from investing activities:
Capital expenditures	0	0	0
Investment in unconsolidated subsidiaries	0	0	0
Cash used for business acquisition	0	0	0
Other investing activities, net	0	0	0
Net cash used in investing activities	0	0	0
Cash flows from financing activities:
Financial Services borrowings	0	0	0
Proceeds from debt issuance	1,991,937	498,087
Repayments of debt	(965,245)	(237,995)	(249,765)
Borrowings under revolving credit facility	619,000	125,000
Repayments under revolving credit facility	(619,000)	(125,000)
Stock option exercises	5,845	10,535	15,627
Share repurchases	(603,206)	(442,738)	(253,019)
Dividends paid	(124,666)	(115,958)	(75,646)
Intercompany activities, net	(561,387)	90,959	46,419
Net cash provided by (used in) financing activities	(256,722)	(197,110)	(516,384)
Net increase (decrease)	0	(11,164)	(309,899)
Cash, cash equivalents, and restricted cash at beginning of period	0	11,164	321,063
Cash, cash equivalents, and restricted cash at end of period	0	0	11,164
Guarantor Subsidiaries [Member]
Net cash provided by (used in) operating activities	(102,054)	(430,940)	174,293
Cash flows from investing activities:
Capital expenditures	(36,297)	(41,857)	(44,956)
Investment in unconsolidated subsidiaries	(14,539)	(454)	0
Cash used for business acquisition	(430,458)	0	(82,419)
Other investing activities, net	11,189	2,391	8,274
Net cash used in investing activities	(470,105)	(39,920)	(119,101)
Cash flows from financing activities:
Financial Services borrowings	0	0	0
Proceeds from debt issuance	4,000	0
Repayments of debt	(21,235)	(1,198)	(866)
Borrowings under revolving credit facility	0	0
Repayments under revolving credit facility	0	0
Stock option exercises	0	0	0
Share repurchases	0	0	0
Dividends paid	0	0	0
Intercompany activities, net	541,703	(27,886)	(87,140)
Net cash provided by (used in) financing activities	524,468	(29,084)	(88,006)
Net increase (decrease)	(47,691)	(499,944)	(32,814)
Cash, cash equivalents, and restricted cash at beginning of period	658,876	1,158,820	1,191,634
Cash, cash equivalents, and restricted cash at end of period	611,185	658,876	1,158,820
Non-Guarantor Subsidiaries [Member]
Net cash provided by (used in) operating activities	(86,398)	(92,596)	(72,897)
Cash flows from investing activities:
Capital expenditures	(2,998)	(3,583)	(3,834)
Investment in unconsolidated subsidiaries	0	0	(9)
Cash used for business acquisition	0	0	0
Other investing activities, net	1,911	8,939	331
Net cash used in investing activities	(1,087)	5,356	(3,512)
Cash flows from financing activities:
Financial Services borrowings	63,744	127,636	34,577
Proceeds from debt issuance	0	0
Repayments of debt	(439)	0	0
Borrowings under revolving credit facility	0	0
Repayments under revolving credit facility	0	0
Stock option exercises	0	0	0
Share repurchases	0	0	0
Dividends paid	0	0	0
Intercompany activities, net	19,684	(63,073)	40,721
Net cash provided by (used in) financing activities	82,989	64,563	75,298
Net increase (decrease)	(4,496)	(22,677)	(1,111)
Cash, cash equivalents, and restricted cash at beginning of period	116,559	139,236	140,347
Cash, cash equivalents, and restricted cash at end of period	112,063	116,559	139,236
Eliminating Entries [Member]
Net cash provided by (used in) operating activities	0	0	0
Cash flows from investing activities:
Capital expenditures	0	0	0
Investment in unconsolidated subsidiaries	0	0	0
Cash used for business acquisition	0	0	0
Other investing activities, net	0	0	0
Net cash used in investing activities	0	0	0
Cash flows from financing activities:
Financial Services borrowings	0	0	0
Proceeds from debt issuance	0	0
Repayments of debt	0	0	0
Borrowings under revolving credit facility	0	0
Repayments under revolving credit facility	0	0
Stock option exercises	0	0	0
Share repurchases	0	0	0
Dividends paid	0	0	0
Intercompany activities, net	0	0	0
Net cash provided by (used in) financing activities	0	0	0
Net increase (decrease)	0	0	0
Cash, cash equivalents, and restricted cash at beginning of period	0	0	0
Cash, cash equivalents, and restricted cash at end of period	$ 0	$ 0	$ 0