Quarterly report pursuant to Section 13 or 15(d)

DERIVATIVES - Derivatives Notional Amount (Details)

v3.10.0.1
DERIVATIVES - Derivatives Notional Amount (Details) - Not Designated as Hedging Instrument - USD ($)
9 Months Ended
Sep. 30, 2018
Dec. 31, 2017
Interest Rate Caps    
Derivative [Line Items]    
Derivative asset, notional amount $ 162,500,000 $ 772,500,000
Weighted average maturity (in months) 4 months  
Interest Rate Swaps    
Derivative [Line Items]    
Derivative liability, notional amount $ 4,242,000,000 0
Weighted average maturity (in months) 50 months  
Weighted average fixed pay rate 2.93%  
Interest Rate Lock Commitments    
Derivative [Line Items]    
Derivative asset, notional amount $ 572,654,000 0
Forward Loan Sale Commitments    
Derivative [Line Items]    
Derivative asset, notional amount 28,402,000 0
TBAs | Short    
Derivative [Line Items]    
Derivative asset, notional amount 5,466,100,000 3,101,100,000
TBAs | Long    
Derivative [Line Items]    
Derivative asset, notional amount $ 4,207,800,000 $ 1,014,000,000
Interest Rate Cap, Contract Two    
Derivative [Line Items]    
Derivative, cap interest rate 4.00%  
Notional amount of derivatives $ 162,500,000.0