Summary Of Significant Accounting Policies (Cost And Carrying Value Of Property Plant And Equipment) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Property, Plant and Equipment [Line Items]
Property and equipment, net	$ 36,288	$ 40,826
Accumulated Depreciation [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	21,266	16,999
Cost [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	57,554	57,825
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	1,419	2,136
Leasehold Improvements [Member] | Accumulated Depreciation [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	5,483	5,889
Leasehold Improvements [Member] | Cost [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	6,902	8,025
Airplane [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	23,491	24,040
Airplane [Member] | Accumulated Depreciation [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	5,506	4,957
Airplane [Member] | Cost [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	28,997	28,997
Computer Software And Equipment [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	11,133	14,374
Computer Software And Equipment [Member] | Accumulated Depreciation [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	8,586	4,109
Computer Software And Equipment [Member] | Cost [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	19,719	18,483
Other [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	245	276
Other [Member] | Accumulated Depreciation [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	1,691	2,044
Other [Member] | Cost [Member]
Property, Plant and Equipment [Line Items]
Property and equipment, net	$ 1,936	$ 2,320