SEGMENT AND GEOGRAPHIC DATA Geographic Data Reporting (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended				6 Months Ended
	Jun. 30, 2013		Jun. 30, 2012		Jun. 30, 2013		Jun. 30, 2012		Dec. 31, 2012
Segment Reporting Information [Line Items]
Revenue	$ 171,360	[1]	$ 204,838	[1]	$ 337,037	[1]	$ 405,428	[1]
Long-lived assets, net of accumulated depreciation and amortization	18,737	[2]	23,309	[2]	18,737	[2]	23,309	[2]
Net assets	88,208		106,989		88,208		106,989		106,541
United Kingdom
Segment Reporting Information [Line Items]
Revenue	45,685	[1]	53,644	[1]	92,763	[1]	105,652	[1]
Long-lived assets, net of accumulated depreciation and amortization	3,457	[2]	3,190	[2]	3,457	[2]	3,190	[2]
Net assets	22,113		24,826		22,113		24,826
Australia
Segment Reporting Information [Line Items]
Revenue	46,188	[1]	59,003	[1]	88,230	[1]	116,647	[1]
Long-lived assets, net of accumulated depreciation and amortization	7,144	[2]	9,747	[2]	7,144	[2]	9,747	[2]
Net assets	25,579		29,463		25,579		29,463
United States
Segment Reporting Information [Line Items]
Revenue	37,124	[1]	44,936	[1]	74,076	[1]	89,572	[1]
Long-lived assets, net of accumulated depreciation and amortization	3,523	[2]	4,571	[2]	3,523	[2]	4,571	[2]
Net assets	20,213		29,102		20,213		29,102
Continental Europe
Segment Reporting Information [Line Items]
Revenue	25,480	[1]	28,685	[1]	50,655	[1]	57,726	[1]
Long-lived assets, net of accumulated depreciation and amortization	1,020	[2]	1,567	[2]	1,020	[2]	1,567	[2]
Net assets	6,184		7,888		6,184		7,888
Other Asia Pacific
Segment Reporting Information [Line Items]
Revenue	16,680	[1]	18,019	[1]	30,840	[1]	34,747	[1]
Long-lived assets, net of accumulated depreciation and amortization	3,546	[2]	4,171	[2]	3,546	[2]	4,171	[2]
Net assets	13,652		15,156		13,652		15,156
Other Americas
Segment Reporting Information [Line Items]
Revenue	203	[1]	551	[1]	473	[1]	1,084	[1]
Long-lived assets, net of accumulated depreciation and amortization	47	[2]	63	[2]	47	[2]	63	[2]
Net assets	$ 467		$ 554		$ 467		$ 554

[1] Revenue by geographic region disclosed above is net of any inter-segment revenue and, therefore, represents only revenue from external customers according to the location of the operating subsidiary.

[2] Comprised of property and equipment and intangibles. Corporate assets are included in the United States.