Segment Information (Schedule of Long-Lived Assets, by Geographical Areas) (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Long Lived Assets	$ 109,428	$ 109,441
United States [Member]
Segment Reporting Information [Line Items]
Long Lived Assets	55,661	56,294
Canada [Member]
Segment Reporting Information [Line Items]
Long Lived Assets	48,771	48,423
Europe [Member]
Segment Reporting Information [Line Items]
Long Lived Assets	3,647	3,228
International Waters [Member]
Segment Reporting Information [Line Items]
Long Lived Assets	1,349	1,496
International [Member]
Segment Reporting Information [Line Items]
Long Lived Assets	$ 53,767	$ 53,147