Derivatives (Summary Of The Change In Fair Value Of The Equity Index Put Option Contracts Found On The Company's Statement Of Operations And Comprehensive Income (Loss)) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014
Option Indexed to Issuer's Equity [Line Items]
Net derivative gain (loss)	$ 6,445	$ 3,774	$ 6,203	$ 2,113
Equity Index Put Option Contracts [Member] | Derivatives Not Designated As Hedging Instruments [Member]
Option Indexed to Issuer's Equity [Line Items]
Net derivative gain (loss)	$ 6,445	$ 3,774	$ 6,203	$ 2,113