Debt and Credit Arrangements (Tables)

9 Months Ended

Sep. 30, 2012

Debt Disclosure [Abstract]

Convertible Notes Payable Components

The following table represents the principal balance, the unamortized discount and the net carrying amount of the liability component and the carrying amount of the equity component of the Convertible Notes:

	September 30, 2012			December 31, 2011
Principal balance of liability component	$	250,000		$	250,000
Unamortized discount	(68,735		)	(75,526		)
Carrying amount of liability component	$	181,265		$	174,474
Equity component, net of deferred taxes	$	75,826		$	75,502