Geographic Information (Long-Lived Assets By Geographic Areas) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Segment Reporting Information [Line Items]
Long-Lived Assets	$ 667,323	$ 529,176	$ 448,810
United States [Member]
Segment Reporting Information [Line Items]
Long-Lived Assets	632,783	495,609	426,329
Canada [Member]
Segment Reporting Information [Line Items]
Long-Lived Assets	22,572	15,954	11,105
Other Foreign Countries [Member]
Segment Reporting Information [Line Items]
Long-Lived Assets	$ 11,968	$ 17,613	$ 11,376