NON-COVERED LOANS AND ALLOWANCE FOR LOAN LOSSES (Details 2) (USD $)			9 Months Ended				3 Months Ended		9 Months Ended				3 Months Ended		9 Months Ended		3 Months Ended		9 Months Ended			9 Months Ended
	Sep. 30, 2014	Dec. 31, 2013	Sep. 30, 2014 Multifamily Minimum Non-covered loans	Sep. 30, 2014 Multifamily Maximum Non-covered loans	Sep. 30, 2014 Residential Minimum Non-covered loans item	Sep. 30, 2014 Residential Maximum Non-covered loans item	Sep. 30, 2014 Residential Single-family Non-covered loans	Sep. 30, 2013 Residential Single-family Non-covered loans	Sep. 30, 2014 Residential Single-family Non-covered loans	Sep. 30, 2013 Residential Single-family Non-covered loans	Sep. 30, 2014 Residential Single-family Minimum Non-covered loans	Sep. 30, 2014 Residential Single-family Maximum Non-covered loans	Sep. 30, 2014 Residential Multifamily Non-covered loans	Sep. 30, 2013 Residential Multifamily Non-covered loans	Sep. 30, 2014 Residential Multifamily Non-covered loans	Sep. 30, 2013 Residential Multifamily Non-covered loans	Sep. 30, 2014 Residential Home Equity Non-covered loans	Sep. 30, 2013 Residential Home Equity Non-covered loans	Sep. 30, 2014 Residential Home Equity Non-covered loans	Sep. 30, 2013 Residential Home Equity Non-covered loans	Sep. 30, 2014 Residential Home Equity Minimum Non-covered loans item	Sep. 30, 2014 Residential Home Equity Maximum Non-covered loans item
Non-Covered loans receivable disclosures
Accrued interest on covered and non-covered loans receivable	$ 72,800,000	$ 94,500,000
Covered and non-covered loans receivable pledged to secure borrowings from the FHLB and the Federal Reserve Bank	13,940,000,000	10,570,000,000
Number of units of residential property securing fixed and adjustable rate first mortgage loans					1	4															1	4
New first mortgage loans originated							$ 316,800,000	$ 586,800,000	$ 728,300,000	$ 1,260,000,000			$ 76,800,000	$ 90,000,000	$ 231,500,000	$ 194,200,000	$ 217,000,000	$ 320,600,000	$ 710,300,000	$ 605,200,000
Adjustable rate mortgage, term of initial fixed interest rates			6 months	3 years							1 year	3 years
Loans to value ratio (as a percent)																						60.00%