Basis of Presentation and Accounting Policy (Deferred Revenues Included In Other Current Liabilities) (Details) (USD $) In Thousands, unless otherwise specified	9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Movement in Deferred Revenue [Roll Forward]
Balance at beginning of period	$ 9,968	$ 21,045
Revenues deferred during the period	21,794	6,518
Revenues recognized during the period	(14,975)	(13,313)
Balance at end of period	16,787	14,234
Deferred Revenue, Period Increase (Decrease)	$ 0	$ (16)