CONDENSED CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net income (loss)	$ 123,865	$ (105,381)
Adjustments to reconcile net income/(loss) to net cash from operating activities
Depreciation and amortization	10,818	11,133
Provision for doubtful accounts / advances	1,354	78
Realized gains on sales of short-term investments	(807)	(5,461)
Deferred income taxes	(9,064)	5,533
Compensation expense related to restricted stock	6,725	5,334
Unrealized foreign exchange (income)	(695)	(2,159)
Changes in assets and liabilities:
Accounts receivable and revenue earned in excess of billings	6,933	18,301
Other current assets	(2,025)	9,845
Accounts payable, income tax payable, accrued payroll and other liabilities	6,089	50,845
Deferred revenue	(4,537)	(4,429)
Net cash provided/(used in) by operating activities	138,656	(16,361)
CASH FLOWS FROM INVESTING ACTIVITIES:
Property and equipment expenditures	(6,622)	(15,368)
Proceeds from sale of property and equipment	204	228
Purchase of mutual funds	(183,198)	(127,303)
Purchase of term deposits with banks	(1,545)	(223,836)
Proceeds from sales of mutual funds	167,254	242,026
Maturities of term deposits with banks	7,644	620,178
Net cash (used in)/ provided by investing activities	(16,263)	495,925
CASH FLOWS FROM FINANCING ACTIVITIES:
Excess tax benefits on stock-based compensation plans		168
Proceeds from loans and borrowings		540,250
Repayment of loans and borrowings	(111,250)	(190,000)
Fees paid relating to loans and borrowing		(1,026)
Dividend paid		(1,261,500)
Repurchase of Common Stock	(16,078)
Net cash (used in) financing activities	(127,328)	(912,108)
Effect of foreign currency exchange rate changes on cash	2,020	(2,711)
Change in cash and cash equivalents	(2,915)	(435,255)
Cash and cash equivalents, beginning of period	78,332	500,499
Cash and cash equivalents, end of period	75,417	65,244
Supplemental disclosures of cash flow information:
Cash paid for income taxes	28,732	263,332
Cash paid for interest	$ 10,433	$ 1,376