CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Cash flows from operating activities:
Net income	$ 11,452	$ 17,469
Adjustments to reconcile net income to net cash from operating activities:
Depreciation and amortization	30,407	26,976
Non-cash interest expense	307	253
Non-cash stock compensation expense	7,646	10,140
Non-cash income tax (benefit) provision	62	(1,010)
Non-cash amortization on investments	809	1,112
Changes in assets and liabilities, net of effects from acquisitions of businesses:
Accounts receivable, net	(87,178)	(27,699)
Pharmaceutical inventory	3,067	(3,379)
Other assets	(37,914)	(1,172)
Accounts payable and accrued liabilities	26,529	(52,838)
Medical claims payable and other medical liabilities	107,569	(5,160)
Contingent consideration	233	(49)
Tax contingencies	448	506
Deferred credits and other long-term liabilities	17,685	4,150
Other	(90)	(421)
Net cash (used in) provided by operating activities	81,032	(31,122)
Cash flows from investing activities:
Capital expenditures	(19,502)	(10,939)
Acquisitions and investments in businesses, net of cash acquired		(200)
Purchase of investments	(142,886)	(141,432)
Maturity of investments	118,999	131,840
Net cash used in investing activities	(43,389)	(20,731)
Cash flows from financing activities:
Proceeds from issuance of debt		200,000
Proceeds from exercise of stock options	16,897	4,945
Payments on debt and capital lease obligations	(55,895)	(182,738)
Other	(3,051)	(1,275)
Net cash provided by (used in) financing activities	(42,049)	20,932
Net decrease in cash and cash equivalents	(4,406)	(30,921)
Cash and cash equivalents at beginning of period	398,732	304,508
Cash and cash equivalents at end of period	394,326	273,587
Non-cash investing activities:
Property and equipment acquired under capital leases	$ 51	$ 906