Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018
Cash flows from operating activities
Net income	$ 154,629	$ 127,021
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	19,127	17,232
Amortization of operating lease right-of-use assets	4,304
Stock-based compensation expense	19,069	11,551
Deferred taxes	73	162
Other	886	2,005
Changes in operating assets and liabilities:
(Increase) in accounts receivable	(15,479)	(9,560)
Decrease in prepaid expenses and other assets	3,855	97
Decrease (Increase) in trading securities	(371)	6,671
(Decrease) in accrued employee compensation	(3,971)	(5,034)
(Decrease) in income and other tax liabilities	(3,279)	(755)
Increase in deferred revenue	921	1,125
(Decrease) increase in accounts payable, accrued expenses and other liabilities	(2,000)	4,614
Increase in operating lease liabilities	800
Net cash provided by operating activities	176,794	153,812
Cash flows from investing activities
Proceeds from maturities and sales, available-for-sale investments	156,809	256,301
Purchases, available-for-sale investments	(149,575)	(260,318)
Purchases of furniture, equipment and leasehold improvements	(8,683)	(23,821)
Capitalization of software development costs	(13,863)	(9,171)
Other	22	25
Net cash (used in) investing activities	(15,290)	(36,984)
Cash flows from financing activities
Cash dividend on common stock	(57,233)	(46,893)
Exercise of stock options	885	1,387
Withholding tax payments on restricted stock vesting and stock option exercises	(18,271)	(7,940)
Repurchases of common stock	(11,440)	(18,985)
Net cash (used in) financing activities	(86,059)	(72,431)
Effect of exchange rate changes on cash and cash equivalents	(1,261)	(1,326)
Cash and cash equivalents including restricted cash
Net increase for the period	74,184	43,071
Beginning of period	247,458	168,150
End of period	321,642	211,221
Non-cash activity
Operating lease right-of-use assets obtained in exchange for operating lease liabilities	422
Mutual Funds Held In Rabbi Trust [Member]
Changes in operating assets and liabilities:
Decrease (Increase) in trading securities	$ (1,770)	$ (1,317)

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 4
-Subparagraph (g)(2)
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980

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