Supplemental Cash Flow Information (Summary Of Supplemental Cash Flow Information) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Cash Paid During The Period For
Interest	$ 28,378	$ 14,786	$ 13,815
Income taxes, net of refunds	7,756	19,615	10,232
Noncash Investing and Financing Activities
Increase (decrease) in accounts payable associated with acquisition of property and equipment	884	248	659
Capital lease obligations	$ 738	$ 1,096	$ 466