Quarterly report pursuant to Section 13 or 15(d)

DERIVATIVE FINANCIAL INSTRUMENTS - Asset and Liability Management (Details)

v3.19.1
DERIVATIVE FINANCIAL INSTRUMENTS - Asset and Liability Management (Details) - USD ($)
$ in Thousands
Mar. 31, 2019
Dec. 31, 2018
Notional Disclosures [Abstract]    
Derivative, Notional Amount $ 9,552,000 $ 4,877,000
Fair Value Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 5,790,000 4,865,000
Cash Flow Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 2,762,000 12,000
Economic Hedging [Member]    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 1,000,000  
Loan    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 2,750,000  
Loan | Fair Value Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 0  
Loan | Cash Flow Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 2,750,000  
Loan | Economic Hedging [Member]    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 0  
Securities Investment [Member]    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 12,000 12,000
Securities Investment [Member] | Fair Value Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 0 0
Securities Investment [Member] | Cash Flow Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 12,000 12,000
Securities Investment [Member] | Economic Hedging [Member]    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 0  
Other long-term debt    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 5,790,000 4,865,000
Other long-term debt | Fair Value Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 5,790,000 4,865,000
Other long-term debt | Cash Flow Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 0 0
Other long-term debt | Economic Hedging [Member]    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 0  
Unassigned [Member]    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 1,000,000  
Unassigned [Member] | Fair Value Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 0  
Unassigned [Member] | Cash Flow Hedging    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 0  
Unassigned [Member] | Economic Hedging [Member]    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 1,000,000  
Asset conversion swaps Receive Fixed Generic    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 12,000 12,000
Liability conversion swaps Receive Fixed Generic    
Notional Disclosures [Abstract]    
Derivative, Notional Amount 5,790,000 $ 4,865,000
Interest Rate Floor [Member]    
Notional Disclosures [Abstract]    
Derivative, Notional Amount $ 3,750,000