Consolidated Statements Of Cash Flows (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Cash Flows from Operating Activities:
Net Income	$ 289,017	$ 235,658	$ 200,531
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	176,483	151,227	153,651
Deferred income tax provision	20,654	7,502	31,184
Net gain on sales of property and equipment	(584)	(24,188)	(2,758)
Noncash compensation	16,442	12,529	8,490
Distributions from unconsolidated affiliates greater than earnings	6,988	2,262	5,569
Excluding the effects of acquisitions, increase (decrease) in cash from:
Accounts receivable	(94,237)	(99,537)	12,104
Inventory	(76,186)	(11,492)	(827)
Other operating assets	(20,278)	(62)	(30,074)
Currency translation effect on working capital	11,318	(10,589)	6,519
Accounts payable and accrued liabilites	87,453	8,968	56,100
Income taxes payable	23,559	14,484	(6,485)
Other operating liabilities	(1,735)	1,810	7,846
Total adjustments to net income	149,877	52,914	241,319
Net Cash Provided by Operating Activities	438,894	288,572	441,850
Cash Flows from Investing Activities:
Purchases of property and equipment	(300,598)	(235,028)	(185,262)
Business acquisitions, net of cash acquired	(9,260)	(291,617)	(21,918)
Dispositions of property and equipment and equity investment	3,814	43,874	15,284
Net Cash Used in Investing Activities	(306,044)	(482,771)	(191,896)
Cash Flows from Financing Activities:
Net Proceeds (payments) from revolving credit facility	(27,045)	120,000	(100,000)
Payments of 6.72% Senior Notes	0	0	(20,000)
Proceeds from issuance of common stock	0	0	693
Excess tax benefits from stock-based compensation	2,475	1,320	1,741
Cash dividends	(74,515)	(48,707)	0
Purchases of treasury stock	(19,358)	(17,491)	(49,520)
Net Cash Provided by (Used in) Financing Activities	(118,443)	55,122	(167,086)
Net Increase (Decrease) in Cash and Cash Equivalents	14,407	(139,077)	82,868
Cash and Cash Equivalents-Beginning of Period	106,142	245,219	162,351
Cash and Cash Equivalents-End of Period	$ 120,549	$ 106,142	$ 245,219