Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2017	Mar. 31, 2016
Cash flows from operating activities:
Net income	$ 63,899	$ 95,936
Adjustments to reconcile net income to net cash flow from operating activities:
Depreciation and amortization	52,105	50,635
Stock-based compensation	5,103	4,757
Other losses on sales of assets and impairment charges	885	5,135
Equity loss (income) in unconsolidated investments, net	1,469	(2,933)
Pension expense, net of contributions	(1,350)	(752)
Change in other assets and liabilities, net	18,777	(25,720)
Net cash flow from operating activities	140,888	127,058
Cash flows from investing activities:
Purchase of property and equipment	(17,959)	(16,449)
Payments for acquisitions of businesses, net of cash acquired	0	(53,059)
Payments for investments	(775)	(10,047)
Proceeds from investments	502	4,617
Proceeds from sale of assets	4,535	0
Net cash flow used for investing activities	(13,697)	(74,938)
Cash flows from financing activities:
(Payments) proceeds of borrowings under revolving credit facilities, net	(46,000)	42,000
Debt repayments	(33,062)	(18,062)
Dividends paid	(29,998)	(30,853)
Repurchases of common stock	(7,252)	(75,411)
Other, net	(8,144)	(19,788)
Net cash flow used for financing activities	(124,456)	(102,114)
Increase (decrease) in cash and cash equivalents	2,735	(49,994)
Balance of cash and cash equivalents at beginning of period	76,920	129,200
Balance of cash and cash equivalents at end of period	79,655	79,206
Supplemental cash flow information:
Cash paid for income taxes, net of refunds	6,518	27,430
Cash paid for interest	$ 34,185	$ 35,261