ACCRUED LIABILITIES (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Accrued liabilities consist of:
Bonuses and accrued vacation	$ 4,881	$ 7,098
Auditing and consulting services	789	1,274
Tax contingencies and accruals for unrecognized income tax benefits	6,498	10,303
Accruals for acquisitions		6,777
Accrued equity-based incentive awards	4,487	3,933
Other accrued liabilities	4,671	4,218
Total accrued liabilities	$ 21,326	$ 33,603