Debt Schedule of Interest Expense On Liability Components (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2012	Mar. 31, 2011
Debt Instrument [Line Items]
Amortization of the discount on the liability component	$ 0	$ 2,643
Convertible Subordinated Debt [Member]
Debt Instrument [Line Items]
Contractual interest coupon	0	1,398
Amortization of the discount on the liability component	0	2,643
Total interest expense on convertible notes	$ 0	$ 4,041