Note 13 - Fair Value of Financial Instruments (Tables)
12 Months Ended
Dec. 31, 2013
Fair Value Disclosures [Abstract]  
Fair Value, Assets Measured on Recurring Basis [Table Text Block]
   

Measured at Fair Value on a Recurring Basis at

 
   

December 31, 2013

   

December 31, 2012

 
   

Level 1

   

Level 2

   

Level 3

   

Total

   

Level 1

   

Level 2

   

Level 3

   

Total

 

Assets carried at fair value

                                                               

Investment securities available for sale:

                                                               

Agency RMBS

  $     $ 876,874     $     $ 876,874     $     $ 1,001,239     $     $ 1,001,239  

Non-Agency RMBS

          2,361             2,361             2,687             2,687  

CLOs

          33,208             33,208             30,785             30,785  

Investment securities available for sale held in securitization trusts:

                                                               

CMBS

                92,578       92,578                   71,159       71,159  

Multi-family loans held in securitization trusts

                8,111,022       8,111,022                   5,442,906       5,442,906  

Derivative Assets:

                                                       

TBA Securities

          190,742             190,742             244,789             244,789  

Options on U.S. Treasury futures

    7                   7             59             59  

U.S. Treasury futures

    3,257                   3,257       676                   676  

Interest rate swap futures

    238                   238       8                   8  

Interest rate swaps

          2,041             2,041                          

Swaptions

          1,305             1,305             597             597  

Total

  $ 3,502     $ 1,106,531     $ 8,203,600     $ 9,313,633     $ 684     $ 1,280,156     $ 5,514,065     $ 6,794,905  

Liabilities carried at fair value

                                                               

Multi-family collateralized debt obligations

  $     $     $ 7,871,020     $ 7,871,020     $     $     $ 5,319,573     $ 5,319,573  

Derivative liabilities:

                                                               

Interest rate swaps

                                  1,744             1,744  

Eurodollar futures

    1,432                   1,432       3,798                   3,798  

Total

  $ 1,432     $     $ 7,871,020     $ 7,872,452     $ 3,798     $ 1,744     $ 5,319,573     $ 5,325,115  
Fair Value, Liabilities Measured on Recurring Basis, Unobservable Input Reconciliation [Table Text Block]
   

Years Ended December 31,

 
   

2013

   

2012

   

2011

 

Balance at beginning of period

  $ 5,514,065     $ 41,185     $  

Total gains (realized/unrealized)

                       

Included in earnings (1)

    (470,467

)

    167,094        

Included in other comprehensive income

    15,532       3,768       (1,036

)

Purchases

    3,218,301       4,212,009       42,221  

Paydowns

    (73,831

)

    (28,034

)

     

Transfers (2)

          1,118,043        

Balance at the end of period

  $ 8,203,600     $ 5,514,065     $ 41,185  
   

Years Ended December 31,

 
   

2013

   

2012

   

2011

 

Balance at beginning of period

  $ 5,319,573     $     $  

Total gains (realized/unrealized)

                       

Included in earnings (1)

    (521,416

)

    152,440        

Included in other comprehensive income

                 

Purchases

    3,146,676       4,077,276        

Paydowns

    (73,813

)

    (28,034

)

     

Transfers (2)

          1,117,891        

Balance at the end of period

  $ 7,871,020     $ 5,319,573     $  
Schedule of Changes in Unrealized Gains (Losses) Included in Earnings for Level 3 Assets and Liabilities [Table Text Block]
   

Years Ended December 31,

 
   

2013

   

2012

   

2011

 

Change in unrealized gains (losses) – assets

  $ (423,949

)

  $ 194,363     $  

Change in unrealized gains (losses) – liabilities

    455,444       (187,701

)

     

Net change in unrealized gains included in earnings for assets and liabilities

  $ 31,495     $ 6,662     $  
Fair Value Measurements, Nonrecurring [Table Text Block]
   

Assets Measured at Fair Value on a Non-Recurring Basis at

 
   

December 31, 2013

   

December 31, 2012

 
   

Level 1

   

Level 2

   

Level 3

   

Total

   

Level 1

   

Level 2

   

Level 3

   

Total

 

Residential Mortgage loans held in securitization trusts – impaired loans (net)

  $       $       $ 6,591     $ 6,591     $     $     $ 5,059     $ 5,059  

Real estate owned held in residential securitization trusts

                    1,108       1,108                   732       732  
Fair Value, Assets Measured on Recurring and Nonrecurring Basis [Table Text Block]
   

Years Ended December 31,

 
   

2013

   

2012

   

2011

 
                         

Residential mortgage loans held in securitization trusts – impaired loans (net)

  $ 701     $ 707     $ 1,380  

Real estate owned held in residential securitization trusts

    433       45       87  
Investment [Table Text Block]
     

December 31, 2013

   

December 31, 2012

 
 

Fair Value

Hierarchy Level

 

Carrying

Value

   

Estimated

Fair Value

   

Carrying

Value

   

Estimated

Fair Value

 

Financial Assets:

                                 

Cash and cash equivalents

Level 1

  $ 31,798     $ 31,798     $ 31,777     $ 31,777  

Investment securities available for sale

Level 2

    912,443       912,443       1,034,711       1,034,711  

Investment securities available for sale, at fair value held in securitization trusts

Level 3

    92,578       92,578       71,159       71,159  

Residential mortgage loans held in securitization trusts (net)

Level 3

    163,237       152,104       187,229       165,919  

Distressed residential mortgage loans (net) (1)

Level 3

    264,434       254,543       60,459       60,459  

Multi-family loans held in securitization trusts

Level 3

    8,111,022       8,111,022       5,442,906       5,442,906  

Derivative assets

Level 1 or 2

    197,590       197,590       246,129       246,129  

Mortgage loans held for sale (net) (2)

Level 3

    2,496       2,595       2,837       2,837  

First mortgage loans (2)

Level 3

    8,249       8,318       1,755       1,775  

Mezzanine loan and equity investments (2)

Level 3

    21,568       21,812       3,522       3,522  
                                   

Financial Liabilities:

                                 

Financing arrangements, portfolio investments

Level 2

  $ 791,125     $ 791,125     $ 889,134     $ 889,134  

Residential collateralized debt obligations

Level 3

    158,410       151,910       180,979       160,506  

Multi-family collateralized debt obligations

Level 3

    7,871,020       7,871,020       5,319,573       5,319,573  

Securitized debt

Level 3

    304,964       311,535       117,591       118,402  

Derivative liabilities

Level 1 or 2

    1,432       1,432       5,542       5,542  

Payable for securities purchased

Level 1

    191,592       191,592       245,931       245,931  

Subordinated debentures

Level 3

    45,000       39,310       45,000       34,108