Geographic Information (Revenue by Geographic Locations) (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014 Reportable_Segments	Jun. 30, 2013
Segment Reporting [Abstract]
Number of reportable segments			1
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues	$ 51,476	$ 51,004	$ 102,880	$ 103,570
Long-lived assets	470,357	456,195	470,357	456,195
United States
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues			69,260	70,898
Long-lived assets	314,673	320,353	314,673	320,353
Canada
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues			2,743	3,381
Long-lived assets	8,670	9,103	8,670	9,103
Latin America
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues			2,981	2,786
Long-lived assets	11,503	11,535	11,503	11,535
Australia
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues			19,310	19,840
Long-lived assets	750	1,007	750	1,007
Singapore
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues			2,260	1,383
Long-lived assets	68,402	69,580	68,402	69,580
New Zealand
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues			1,353	1,161
Long-lived assets	94	209	94	209
India
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues			549	371
Long-lived assets	37,449	19,388	37,449	19,388
Europe
Revenues from External Customers and Long-Lived Assets [Line Items]
External Revenues			4,424	3,750
Long-lived assets	$ 28,816	$ 25,020	$ 28,816	$ 25,020