Derivative Contracts (Details) (Not Designated as Hedging Instrument [Member], USD $) In Thousands, unless otherwise specified	Mar. 31, 2014		Dec. 31, 2013
Common stock options/warrants [Member] | Investments, net [Member]
Derivatives, Fair Value [Line Items]
Derivative asset, fair value	$ 6,797		$ 5,988
Embedded conversion option [Member] | 2033 Senior Notes, net of discount and estimated fair value of embedded derivatives [Member]
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	112,199		101,087
Forward contracts [Member]
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	2,436		1,585
Forward contracts [Member] | Current portion of lines of credit and notes payable [Member]
Derivatives, Fair Value [Line Items]
Derivative liability, fair value	$ 2,436	[1]	$ 1,585	[1]

[1] The loss on forward contracts is recorded in Accrued expenses. The gain on the forward contracts is recorded in Prepaid expenses and other current assets.