CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013
Cash flows from operating activities:
Net income	$ 28,707	$ 59,538
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	42,709	33,116
Non-cash interest expense	1,572	368
Non-cash stock compensation expense	14,022	10,240
Non-cash income tax expense (benefit)	(1,558)	1,335
Non-cash amortization on investments	2,653	4,884
Realized loss on sale of investments	50
Cash flows from changes in assets and liabilities, net of effects from acquisitions of businesses:
Restricted cash	69,383	37,086
Accounts receivable, net	(15,752)	(27,361)
Pharmaceutical inventory	5,332	(4,150)
Other assets	(27,675)	(8,281)
Accounts payable and accrued liabilities	(5,434)	(29,643)
Medical claims payable and other medical liabilities	18,657	6,384
Tax contingencies	1,164	1,349
Deferred credits and other long-term liabilities	3,366	373
Other	(145)	1,671
Net cash provided by operating activities	137,051	86,909
Cash flows from investing activities:
Capital expenditures	(32,007)	(27,035)
Acquisitions and investments in businesses, net of cash acquired	(124,995)	(7,900)
Purchase of investments	(112,088)	(165,372)
Maturity of investments	146,532	139,068
Net cash used in investing activities	(122,558)	(61,239)
Cash flows from financing activities:
Payments to acquire treasury stock	(65,254)	(49,462)
Proceeds from exercise of stock options and warrants	34,197	16,110
Payments on capital lease obligations	(2,087)	(1,816)
Other	1,241	(747)
Net cash used in financing activities	(31,903)	(35,915)
Net decrease in cash and cash equivalents	(17,410)	(10,245)
Cash and cash equivalents at beginning of period	203,187	189,464
Cash and cash equivalents at end of period	185,777	179,219
Non-cash investing activities:
Property and equipment acquired under capital leases	$ 216	$ 29,323