COMMITMENTS AND CONTINGENCIES (Details 2) (USD $) In Millions, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
Loans Sold or Securitized with Recourse
Guarantees
Principal amount of loans sold or securitized	$ 589.9	$ 699.6
Recourse reserve related to loan sales and securitizations totaled	4.4	4.7
Loans Sold or Securitized with Recourse | Single-family Loans with Full Recourse
Guarantees
Principal amount of loans sold or securitized	54.5	60.9
Loans Sold or Securitized with Recourse | Multi-family Loans with Limited Recourse
Guarantees
Principal amount of loans sold or securitized	535.4	638.7
Recourse provision limitation, maximum percentage of the top loss on the underlying loans	4.00%	4.00%
Loans Sold without Recourse
Guarantees
Principal amount of loans sold or securitized	1,230.0	1,480.0
Loans Securitized without Recourse
Guarantees
Principal amount of loans sold or securitized	$ 273.7	$ 325.5