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Debt And Other Long-Term Liabilities (Narrative) (Details) (USD $)	3 Months Ended	9 Months Ended							3 Months Ended			3 Months Ended
	Sep. 30, 2011	Sep. 30, 2011	Jul. 15, 2011	Dec. 31, 2010	Sep. 30, 2011 Term Loan [Member]	Sep. 30, 2011 Revolving Credit Facility [Member]	Sep. 30, 2011 Minimum [Member] LIBOR Rate [Member]	Sep. 30, 2011 Maximum [Member] LIBOR Rate [Member]	Dec. 31, 2011 LIBOR Rate [Member]	Sep. 30, 2011 Minimum [Member] Base Rate [Member]	Sep. 30, 2011 Maximum [Member] Base Rate [Member]	Dec. 31, 2011 Base Rate [Member]	Sep. 30, 2011 Minimum [Member]
Debt Instrument [Line Items]
Line of credit facility, initiation date		July 15, 2011
Line of credit facility, description years		five
Line of credit facility					$ 175,000,000	$ 450,000,000
Line of credit facility option to increase borrowing capacity	250,000,000	250,000,000
New line of Credit Facility, increase, additional borrowings		175,000,000
Old line of Credit Facility, decrease, repayments		120,000,000
Common stock closing price													$ 130.00%
Number of trading days considered for conversion of notes													20
Number of consecutive trading days considered for conversion of notes	30	30
Fee for revolving line of credit facility		4,200,000
Fees for the New Credit Facility amortization, years			5
Unamortized deferred finance fees	900,000	900,000
Credit facility maturity date		July 15, 2016
Long-term debt maturities repayments of principal percentage in year one		5.00%
Long-term debt maturities repayments of principal percentage in year two		7.50%
Long-term debt maturities repayments of principal percentage in year three		10.00%
Long-term debt maturities repayments of principal percentage in year four and five		12.50%
Principal payments on term loan	2,187,000	2,187,000
Basis spread on variable rate							125.00%	200.00%		25.00%	100.00%
Basis spread on variable rate during Q1 2012									150			50
Term loan interest rate	1.73%	1.73%
Convertible notes payable, face value	200,000,000	200,000,000
Interest rate, per year	4.00%	4.00%
Notes maturity date		Sep. 01, 2014
Note issuance effective interest rate	8.50%	8.50%
Line of credit facility, covenant terms		The New Credit Facility contains standard negative covenants and restrictions on actions including, without limitation, restrictions on indebtedness, liens, fundamental changes or dispositions of our assets, payments of dividends, capital expenditures, investments, and mergers, dispositions and acquisitions, among other restrictions. In addition, the New Credit Facility requires that we meet certain financial covenants, ratios and tests, including maintaining a maximum consolidated net leverage ratio and a minimum interest coverage ratio, as defined in the New Credit Facility.
Convertible debt convenant compliance		As of September 30, 2011, we are in compliance with all covenants
Temporary equity				$ 26,854,000