Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income	$ 46,307	$ 57,277
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	42,059	28,685
Asset impairments		955
Amortization of debt issuance costs and other non-cash interest	792	776
Deferred income taxes	875	637
Non-cash revenue and other income	(496)	(496)
Income tax benefit of equity compensation	(16)	(379)
Non-cash equity compensation	3,781	3,798
Other expenses and non-cash items	787	1,545
Changes in assets and liabilities, net:
Accounts receivable, prepaid expenses and other assets	39,014	22,930
Accounts payable, accrued expenses and other liabilities	(13,311)	1,788
Income taxes payable	517	(330)
Net cash provided by operating activities	120,309	117,186
CASH FLOWS FROM INVESTING ACTIVITIES:
Expenditures for facility development and expansions	(7,793)	(63,366)
Expenditures for other capital improvements	(6,290)	(14,562)
Capitalized lease payments		(16,283)
Acquisition of businesses, net of cash acquired	(1,780)
Decrease in restricted cash	240
Proceeds from sale of assets	139	45
Decrease in other assets	661	2,048
Payments received on direct financing lease and notes receivable	606	537
Net cash used in investing activities	(14,217)	(91,581)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of debt	55,000	70,000
Principal repayments of debt	(101,250)	(30,000)
Payment of debt issuance and other refinancing and related costs	(66)
Payment of lease obligations	(3,260)
Dividends paid	(65,108)	(61,136)
Income tax benefit of equity compensation	16	379
Purchase and retirement of common stock	(3,528)	(9,261)
Decrease in restricted cash for dividends	550	500
Proceeds from exercise of stock options	1,079	3,542
Net cash used in financing activities	(116,567)	(25,976)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(10,475)	(371)
CASH AND CASH EQUIVALENTS, beginning of period	65,291	74,393
CASH AND CASH EQUIVALENTS, end of period	54,816	74,022
Cash paid during the period for:
Interest (net of amounts capitalized of $60 and $1,196 in 2016 and 2015, respectively)	3,602	2,099
Income taxes paid (refunded)	$ (12,028)	$ 1,167