Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2018	Jun. 30, 2017
Operating activities:
Net income (loss)	$ 26,683	$ (55,848)
Adjustments to reconcile net income (loss) to net cash provided by operating activities:
Depreciation and amortization	134,894	100,087
Stock-based compensation expense	45,300	53,573
Deferred taxes	(18,019)	(78,004)
Gain from divested operations	(25,460)	0
Amortization and write-off of deferred financing fees	10,601	9,475
Changes in assets and liabilities, net of acquisitions and divestitures:
Fees receivable, net	81,222	(44,939)
Deferred commissions	21,818	477
Prepaid expenses and other current assets	(82,908)	(22,453)
Other assets	23,862	(17,328)
Deferred revenues	87,316	167,412
Accounts payable, accrued, and other liabilities	(128,562)	(29,734)
Cash provided by operating activities	176,747	82,718
Investing activities:
Additions to property, equipment and leasehold improvements	(40,126)	(41,627)
Acquisitions - cash paid (net of cash acquired)	0	(2,604,178)
Divestitures - cash received (net of cash transferred)	405,542	0
Other	1,000	0
Cash provided by (used in) investing activities	366,416	(2,645,805)
Financing activities:
Proceeds from employee stock purchase plan	7,627	5,662
Proceeds from borrowings	0	2,885,000
Payments for deferred financing fees	0	(51,170)
Payments on borrowings	(858,609)	(119,812)
Purchases of treasury stock	(96,271)	(33,786)
Cash (used in) provided by financing activities	(947,253)	2,685,894
Net (decrease) increase in cash and cash equivalents and restricted cash	(404,090)	122,807
Effects of exchange rates on cash and cash equivalents and restricted cash	(3,012)	10,406
Cash and cash equivalents and restricted cash, beginning of period	159,956	632,567
Cash and cash equivalents and restricted cash, end of period	$ 567,058	$ 499,354