CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Cash Flows from Operating Activities:
Net income	$ 127,907	$ 120,129	$ 30,683
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	18,428	13,261	17,123
Non-cash compensation	25,040	17,887	16,295
401(k) employer match	10,509	8,976	8,754
Amortization and impairment of operating lease right of use assets	35,905	0	0
Loss on disposal of property and equipment	141	714	0
Deferred income taxes	13,466	20,271	52,178
Equity in earnings from equity method investments	(5,338)	(7,692)	(3,381)
Amortization of deferred debt issuance costs/debt discount	873	797	735
Return on equity investment	4,955	6,158	5,321
Asset impairment charge	1,470	0	1,323
Changes in operating assets and liabilities, net of impact of acquisitions:
Patient accounts receivable	(24,146)	12,224	(34,672)
Other current assets	(2,682)	8,679	(4,940)
Other assets	832	2,947	(12,749)
Accounts payable	(11,329)	3,165	(2,843)
Accrued expenses	42,096	13,524	31,843
Other long-term obligations	(329)	2,443	61
Operating lease liabilities	(32,295)	0	0
Operating lease right of use assets	(3,503)	0	0
Net cash provided by operating activities	202,000	223,483	105,731
Cash Flows from Investing Activities:
Proceeds from sale of deferred compensation plan assets	448	715	622
Proceeds from the sale of property and equipment	162	54	249
Purchases of property and equipment	(7,888)	(6,558)	(10,707)
Investments in equity method investees	(210)	(7,144)	(476)
Acquisitions of businesses, net of cash acquired	(345,460)	(9,260)	(33,715)
Net cash used in investing activities	(352,948)	(22,193)	(44,027)
Cash Flows from Financing Activities:
Proceeds from issuance of stock upon exercise of stock options	3,611	5,953	4,554
Proceeds from issuance of stock to employee stock purchase plan	3,187	2,429	2,382
Shares withheld upon stock vesting	(9,556)	(6,570)	(6,939)
Non-controlling interest distribution	(1,062)	(1,090)	(216)
Proceeds from borrowings under term loan	175,000	0	0
Proceeds from borrowings under revolving line of credit	262,500	138,000	0
Repayments of borrowings under revolving line of credit	(200,000)	(130,500)	0
Principal payments of long-term obligations	(5,624)	(91,450)	(5,319)
Debt issuance costs	(847)	(2,433)	0
Purchase of company stock	0	(181,402)	0
Repurchase of noncontrolling interest	0	(361)	0
Net cash provided by (used in) financing activities	227,209	(267,424)	(5,538)
Net increase (decrease) in cash, cash equivalents and restricted cash	76,261	(66,134)	56,166
Cash, cash equivalents and restricted cash at beginning of period	20,229	86,363	30,197
Cash, cash equivalents and restricted cash at end of period	96,490	20,229	86,363
Supplemental Disclosures of Cash Flow Information:
Cash paid for interest	9,628	3,522	2,697
Cash paid for income taxes, net of refunds received	29,522	14,278	315
Supplemental Disclosures of Non-Cash Financing Activities:
Note payable issued for software licenses	$ 0	$ 418	$ 0