Convertible and Non-Recourse Notes (Interest Expense for the Series 2012 Notes) (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Debt Instrument [Line Items]
Amortization of debt issuance costs	$ 12,481	$ 5,386	$ 1,682
Amortization of debt discount	10,170	3,338
Series 2012 Notes [Member]
Debt Instrument [Line Items]
Contractual coupon interest	5,122	0	0
Amortization of debt issuance costs	1,107	0	0
Amortization of debt discount	(5,682)	0	0
Total	$ 11,911	$ 0	$ 0