Investments in Securities - Additional Information (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Investment Securities [Line Items]
Principal amount of unsecured REIT note receivables and CMBS receivables	$ 98,219	$ 101,021
TruPS and subordinated debentures
Investment Securities [Line Items]
Principal amount of TruPS	$ 678,276	$ 678,276

The principal amount of unsecured REIT note receivables and CMBS receivables, which are assets in the consolidated securitizations, that serve as collateral for the debt, CDO notes payable, of the consolidated securitizations.

No definition available.

Name:	ras_PrincipalAmountOfUnsecuredReitNoteReceivablesAndCmbsReceivable
Namespace Prefix:	ras_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant