Operating Expenses (Narrative) (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Property, Plant and Equipment [Line Items]
Impairment loss		$ 8,084
Amortization expense	$ 6,658	4,570	$ 3,625
Depreciation expense	35,374	39,966	$ 39,655
Land and Improvements [Member]
Property, Plant and Equipment [Line Items]
Impairment loss		6,094
Building [Member]
Property, Plant and Equipment [Line Items]
Impairment loss		1,990
Software [Member]
Property, Plant and Equipment [Line Items]
Amortization expense	4,680
Depreciation expense	$ 4,340
Narita, Japan [Member]
Property, Plant and Equipment [Line Items]
Impairment loss		8,084
Narita, Japan [Member] | Land and Improvements [Member]
Property, Plant and Equipment [Line Items]
Impairment loss		6,094
Impaired Asset, Recoverable Amount		16,150
Narita, Japan [Member] | Building [Member]
Property, Plant and Equipment [Line Items]
Impairment loss		1,990
Impaired Asset, Recoverable Amount		$ 4,779