Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2016	Mar. 31, 2015
Cash flows from operating activities
Net income	$ 11,905	$ 20,035
Adjustment to reconcile net income to net cash provided by operating activities:
Depreciation and amortization	17,729	15,363
Amortization of contract acquisition costs	169	281
Amortization of debt issuance costs	235	178
Imputed interest expense and fair value adjustments to contingent consideration	145	209
Provision for doubtful accounts	218	53
Gain on disposal of assets	(10)	(35)
Deferred income taxes	5,083	(1,479)
Excess tax benefit from equity-based awards	(196)	(409)
Equity-based compensation expense	2,759	2,690
(Gain) loss on foreign currency derivatives	(4,052)	87
Changes in assets and liabilities, net of acquisitions:
Accounts receivable	329	(24,821)
Prepaids and other assets	(9,525)	1,849
Accounts payable and accrued expenses	(11,506)	(7,583)
Deferred revenue and other liabilities	(1,745)	(2,598)
Net cash provided by operating activities	11,538	3,820
Cash flows from investing activities
Proceeds from sale of long-live assets	1
Purchases of property, plant and equipment, net of acquisitions	(14,949)	(13,038)
Investments in non-marketable equity investments		(9,000)
Acquisitions, net of cash acquired of zero and zero, respectively	(200)	(102)
Net cash used in investing activities	(15,148)	(22,140)
Cash flows from financing activities
Proceeds from line of credit	581,500	573,800
Payments on line of credit	(548,500)	(547,800)
Payments on other debt	(550)	(778)
Payments of contingent consideration and hold back payments to acquisitions	(7,628)	(1,000)
Dividends paid to shareholders		(8,710)
Dividends distributed to noncontrolling interest	(900)	(990)
Proceeds from exercise of stock options	6	234
Excess tax benefit from equity-based awards	196	409
Payments of debt issuance costs	(1,883)
Purchase of treasury stock	(8,730)	(5,915)
Net cash used in financing activities	13,511	9,250
Effect of exchange rate changes on cash and cash equivalents	5,217	(2,532)
Increase (decrease) in cash and cash equivalents	15,118	(11,602)
Cash and cash equivalents, beginning of period	60,304	77,316
Cash and cash equivalents, end of period	75,422	65,714
Supplemental disclosures
Cash paid for interest	1,627	1,340
Cash paid for income taxes	7,659	2,803
Non-cash investing and financing activities
Acquisition of long lived assets through capital leases	1,002
Acquisition of equipment through increase in accounts payable, net	(1,257)	$ 1,704
Contract acquisition costs credited to accounts receivable	$ 200