CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017
Cash Flows from Operating Activities:
Net income	$ 92,409	$ 34,389
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	9,882	13,139
Non-cash compensation	12,653	11,788
401(k) employer match	6,934	6,547
Loss (gain) on disposal of property and equipment	738	(22)
Deferred income taxes	14,916	17,228
Equity in earnings from equity method investments	(6,461)	(3,149)
Amortization of deferred debt issuance costs/debt discount	596	555
Return on equity investment	4,373	4,656
Changes in operating assets and liabilities, net of impact of acquisitions:
Patient accounts receivable	6,166	(10,846)
Other current assets	(32)	(5,896)
Other assets	726	(12,202)
Accounts payable	(670)	(5,430)
Accrued expenses	14,758	22,584
Other long-term obligations	2,462	201
Net cash provided by operating activities	159,450	73,542
Cash Flows from Investing Activities:
Proceeds from sale of deferred compensation plan assets	563	622
Proceeds from the sale of property and equipment	51	118
Investments in equity method investees	(3,477)	(436)
Purchases of property and equipment	(5,684)	(9,074)
Acquisitions of businesses, net of cash acquired	(4,074)	(24,128)
Net cash used in investing activities	(12,621)	(32,898)
Cash Flows from Financing Activities:
Proceeds from issuance of stock upon exercise of stock options and warrants	2,749	4,214
Proceeds from issuance of stock to employee stock purchase plan	1,787	1,798
Shares withheld upon stock vesting	(5,421)	(6,454)
Noncontrolling interest distribution	(530)	(216)
Proceeds from borrowings under revolving line of credit	127,500	0
Repayments of borrowings under revolving line of credit	(70,000)	0
Principal payments of long-term obligations	(91,071)	(4,069)
Debt issuance costs	(2,433)	0
Purchase of company stock	(181,402)	0
Repurchase of noncontrolling interest	(361)	0
Net cash used in financing activities	(219,182)	(4,727)
Net (decrease) increase in cash and cash equivalents	(72,353)	35,917
Cash and cash equivalents at beginning of period	86,363	30,197
Cash and cash equivalents at end of period	14,010	66,114
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest	2,989	2,188
Cash paid for income taxes, net of refunds received	$ 11,017	$ 315