Other Accrued Liabilities (Other Accrued Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Dec. 31, 2011
Other Accrued Liabilities [Abstract]
Accrued professional fees	$ 383		$ 322
Straight line rent accrual	3,801		2,928
Other taxes payable	1,803		1,505
Income taxes payable	5,481		3,436
Other liabilities	3,352		3,385
Contingent purchase price	835	[1]	2,394	[1]
Total other accrued liabilities	$ 15,655		$ 13,970

[1] Contingent purchase price relates to the earnout provisions for the BHI acquisition for the period ended June 30, 2012, and the Quorum acquisition for the year ended December 31, 2011 (refer to Footnote 4 - Acquisitions and Footnote 6 - Goodwill for additional information.)