Risks and Uncertainties Related to Liquidity and Capital Resources (Details) (USD $)	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012	Dec. 31, 2012	Dec. 31, 2011
Risks and Uncertainties Disclosures
Cash and cash equivalents	$ 1,608,702,000	$ 1,234,199,000	$ 1,357,212,000	$ 477,469,000
Net loss	(7,415,000)	(47,964,000)
Cash flows from operating and investing activities	323,300,000
Remaining principal and interest payments for 2013	1,500,000,000
Unencumbered personal loans	1,200,000,000
Unencumbered real estate loans	567,900,000
Note receivable from parent	537,989,000		537,989,000
SLFI
Risks and Uncertainties Disclosures
Note receivable from parent	$ 538,000,000		$ 538,000,000