Condensed Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015
Cash flows—operating activities:
Net income	$ 14,920	$ 15,872
Adjustments to reconcile net income to net cash used in operating activities:
Depreciation and amortization	11,676	9,983
Deferred income taxes	(1,731)	(153)
Stock-based compensation expense	5,055	3,684
Accretion expense related to earnout payments	198	861
Changes in assets and liabilities, net of effects of acquisitions:
Accounts receivable	(33,267)	(40,582)
Accounts payable	2,270	(1,311)
Accrued expenses	(47,130)	(5,361)
Deferred revenue	1,298	3,921
Income taxes payable, net	(76)	(3,101)
Retirement and pension plan assets and liabilities	3,009	69
Prepaid expenses	(4,228)	(1,054)
Other assets and liabilities, net	(1,008)	(2,868)
Net cash used in operating activities	(49,014)	(20,040)
Cash flows—investing activities:
Restricted cash	7,228	0
Payments to Acquire Businesses, Gross	(27,722)	0
Capital expenditures	(2,179)	(13,897)
Purchases of available for sale investments	(2,361)	(1,402)
Proceeds from sales of available for sale investments	510	630
Net cash used in investing activities	(24,524)	(14,669)
Cash flows—financing activities:
Debt repayment	0	(29,500)
Debt issuance costs	0	(422)
Cash dividends paid	(7,442)	(7,496)
Payment of employee tax withholdings on equity transactions	(2,676)	(878)
Acquisition earnout payments	(7,461)	(5,496)
Net cash used in financing activities	(17,579)	(43,792)
Effect of exchange rates fluctuations on cash and cash equivalents	640	(3,891)
Net decrease in cash and cash equivalents	(90,477)	(82,392)
Cash and cash equivalents at beginning of period	190,452	211,352
Cash and cash equivalents at end of period	99,975	128,960
Supplemental Schedule of Non-cash Financing Activities:
Term loan facility retirement (Note 12)	0	26,500
Subsequent drawing on line of credit (Note 12)	$ 0	$ 26,500