Derivative Financial Instruments (Details Textual)	3 Months Ended	9 Months Ended			3 Months Ended	9 Months Ended
	Sep. 30, 2012 USD ($)	Sep. 30, 2012 USD ($) agreement	Sep. 30, 2012 AUD	Jan. 01, 2012 USD ($)	Sep. 30, 2012 Fair Value Hedging [Member] Interest Rate Swap [Member] USD ($)	Sep. 30, 2012 Fair Value Hedging [Member] Interest Rate Swap [Member] USD ($)	Sep. 30, 2012 Minimum [Member]	Sep. 30, 2012 Maximum [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Gains (loss) recongized and recorded in earnings related to fair value hedge					$ 300,000	$ 400,000
Interest Rate Swaps [Abstract]
Notes bear interest at a rate	7.75%	7.75%
Notional amount coincide with the terms of the non-recourse debt	100,000,000	100,000,000
Interest Rate Swap Agreements			50,900,000
Variable interest rate payment to the same counterparties							4.16%	4.29%
Ineffective portion of Fair value interest rate swap		0
Derivative Financial Instruments [Abstract]
Number of Interest Rate Swap Agreements		4
Fair value of the swap assets included as Other Non-Current Assests	7,000,000	7,000,000		7,400,000
Fixed interest rate on cash flow interest rate derivative	9.70%	9.70%
Net unrealized loss recognized in the periods and recorded in accumulated other comprehensive income, net of tax	100,000	500,000
Interest Rate Cash Flow Hedge Liability at Fair Value	700,000	700,000
Fair value of the swap assets (liabilities) recorded as a component of other assets (liabilities)				0
Ineffective portion of Cash Flow Hedge interest rate swap		$ 0