Consolidated Statements of Cash Flows (USD $) In Thousands, unless otherwise specified	6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011
Cash flows from operating activities
Net income	$ 23,065	$ 34,595
Adjustment to reconcile net income to net cash provided by operating activities:
Depreciation & Amortization	20,345	23,021
Amortization of contract acquisition costs	508	1,009
Amortization of debt issuance costs	347	290
Imputed interest expense	373	531
Provision for doubtful accounts	48	0
Loss (gain) on disposal of assets	137	(696)
Impairment losses	2,797	230
Deferred income taxes	(8,097)	8,076
Excess tax benefit from equity-based awards	(1,136)	(3,099)
Equity-based compensation expense	6,845	7,715
(Gain) loss on foreign currency derivatives	(963)	531
Changes in assets and liabilities, net of acquisitions:
Accounts receivable	1,095	5,908
Prepaids and other assets	(11,979)	(6,317)
Accounts payable and accrued expenses	13,453	(17,950)
Deferred revenue and other liabilities	1,819	(5,863)
Net cash provided by operating activities	48,657	47,981
Cash flows from investing activities
Proceeds from grant for property, plant and equipment	110	0
Proceeds from sale of long-lived assets	225	2,328
Purchases of property, plant and equipment, net of acquisitions	(17,478)	(12,362)
Acquisitions, net of cash acquired of $1,373 and $14, respectively	(4,809)	(43,884)
Net cash used in investing activities	(21,952)	(53,918)
Cash flows from financing activities
Proceeds from line of credit	515,950	406,100
Payments on line of credit	(501,950)	(288,100)
Proceeds from other debt	6,821	0
Payments on other debt	(1,390)	(1,088)
Dividends distributed to noncontrolling interest	(720)	(1,859)
Proceeds from exercise of stock options	770	3,673
Excess tax benefit from equity-based awards	1,136	3,099
Purchase of treasury stock	(40,732)	(43,748)
Payments of debt issuance costs	(432)	(22)
Net cash (used in) provided by financing activities	(20,547)	78,055
Effect of exchange rate changes on cash and cash equivalents	8,049	2,783
Increase in cash and cash equivalents	14,207	74,901
Cash and cash equivalents, beginning of period	156,371	119,385
Cash and cash equivalents, end of period	170,578	194,286
Supplemental disclosures
Cash paid for interest	1,706	2,026
Cash paid for income taxes	8,546	14,875
Non-cash investing and financing activities
Purchases of equipment through financing arrangements	6,100	0
Grant income credited to property plant and equipment	110	0
Landlord incentives credited to deferred rent	$ 604	$ 0