Annual report pursuant to Section 13 and 15(d)

LONG-TERM DEBT - Schedule of Long-Term Debt (Details)

v3.3.1.900
LONG-TERM DEBT - Schedule of Long-Term Debt (Details) - USD ($)
$ in Thousands
 12 Months Ended
Dec. 31, 2015
Dec. 31, 2014
Debt Instrument [Line Items]    
Long-term borrowings $ 7,067,614 $ 4,335,962
Subordinated Notes    
Debt Instrument [Line Items]    
Long-term borrowings 5,561,529 2,466,665
Subordinated Notes | 6.67% subordinated notes due 2018    
Debt Instrument [Line Items]    
Long-term borrowings $ 136,237 140,115
Stated rate 6.67%  
Subordinated Notes | 5.59% subordinated notes due 2016    
Debt Instrument [Line Items]    
Long-term borrowings $ 103,357 105,731
Stated rate 5.59%  
Subordinated Notes | 5.45% subordinated notes due 2019    
Debt Instrument [Line Items]    
Long-term borrowings $ 83,833 85,783
Stated rate 5.45%  
Senior Notes | 2.24% Huntington National Bank senior note due 2018    
Debt Instrument [Line Items]    
Long-term borrowings $ 845,016 0
Stated rate 2.24%  
Senior Notes | 2.10% Huntington National Bank senior note due 2018    
Debt Instrument [Line Items]    
Long-term borrowings $ 750,035 0
Stated rate 2.10%  
Senior Notes | 1.75% Huntington National Bank senior note due 2018    
Debt Instrument [Line Items]    
Long-term borrowings $ 502,822 0
Stated rate 1.75%  
Senior Notes | 2.23% Huntington National Bank senior note due 2017    
Debt Instrument [Line Items]    
Long-term borrowings $ 502,549 499,759
Stated rate 2.23%  
Senior Notes | 2.43% Huntington National Bank senior note due 2020    
Debt Instrument [Line Items]    
Long-term borrowings $ 500,646 0
Stated rate 2.43%  
Senior Notes | 2.97% Huntington National Bank senior note due 2020    
Debt Instrument [Line Items]    
Long-term borrowings $ 500,489 0
Stated rate 2.97%  
Senior Notes | 1.43% Huntington National Bank senior note due 2019    
Debt Instrument [Line Items]    
Long-term borrowings $ 500,292 499,760
Stated rate 1.43%  
Senior Notes | 1.31% Huntington National Bank senior note due 2016    
Debt Instrument [Line Items]    
Long-term borrowings $ 498,925 497,477
Stated rate 1.31%  
Senior Notes | 1.40% Huntington National Bank senior note due 2016    
Debt Instrument [Line Items]    
Long-term borrowings $ 349,793 349,499
Stated rate 1.40%  
Senior Notes | 0.74% Huntington National Bank senior note due 2017    
Debt Instrument [Line Items]    
Long-term borrowings $ 250,000 250,000
Effective rate 0.74%  
Senior Notes | 5.04% Huntington National Bank medium-term notes due 2018    
Debt Instrument [Line Items]    
Long-term borrowings $ 37,535 38,541
Stated rate 5.04%  
Senior Notes | Three-month LIBOR | 0.74% Huntington National Bank senior note due 2017    
Debt Instrument [Line Items]    
Basis spread on variable rate 0.425%  
Federal Home Loan Bank advances    
Debt Instrument [Line Items]    
Long-term borrowings $ 7,802 758,052
Other borrowings    
Debt Instrument [Line Items]    
Long-term borrowings $ 452,448 65,141
Other borrowings | FHLB advances    
Debt Instrument [Line Items]    
Effective rate 3.46%  
Other borrowings | Huntington Technology Finance nonrecourse debt, 4.21% effective interest rate, varying maturities    
Debt Instrument [Line Items]    
Long-term borrowings $ 301,577 0
Effective rate 4.21%  
Other borrowings | Huntington Technology Finance ABS Trust 2014 1.35% due 2020    
Debt Instrument [Line Items]    
Long-term borrowings $ 123,577 0
Stated rate 1.35%  
Other borrowings | Huntington Technology Finance ABS Trust 2012 1.79% due 2017    
Debt Instrument [Line Items]    
Long-term borrowings $ 27,153 0
Stated rate 1.79%  
Other borrowings | Other    
Debt Instrument [Line Items]    
Long-term borrowings $ 141 65,141
Parent Company    
Debt Instrument [Line Items]    
Long-term borrowings 1,045,835 1,046,104
Parent Company | Subordinated Notes | Fixed 7.00% subordinated notes due 2020    
Debt Instrument [Line Items]    
Long-term borrowings $ 328,185 330,105
Stated rate 7.00%  
Parent Company | Subordinated Notes | Huntington Capital I Trust Preferred 1.03% junior subordinated debentures due 2027    
Debt Instrument [Line Items]    
Long-term borrowings $ 111,816 111,816
Effective rate 1.03%  
Parent Company | Subordinated Notes | Sky Financial Capital Trust IV 1.73% Junior Subordinated Debentures Due 2036 [Member]    
Debt Instrument [Line Items]    
Long-term borrowings $ 74,320 74,320
Effective rate 1.73%  
Parent Company | Subordinated Notes | Sky Financial Capital Trust III 2.01% junior subordinated debentures due 2036    
Debt Instrument [Line Items]    
Long-term borrowings $ 72,165 72,165
Effective rate 2.01%  
Parent Company | Subordinated Notes | Huntington Capital II Trust Preferred 1.14% junior subordinated debentures due 2028    
Debt Instrument [Line Items]    
Long-term borrowings $ 54,593 54,593
Effective rate 1.14%  
Parent Company | Subordinated Notes | Camco Statutory Trust I 2.95% due 2037    
Debt Instrument [Line Items]    
Long-term borrowings $ 4,212 4,181
Effective rate 2.95%  
Parent Company | Subordinated Notes | Three-month LIBOR | Huntington Capital I Trust Preferred 1.03% junior subordinated debentures due 2027    
Debt Instrument [Line Items]    
Basis spread on variable rate 0.70%  
Parent Company | Subordinated Notes | Three-month LIBOR | Sky Financial Capital Trust IV 1.73% Junior Subordinated Debentures Due 2036 [Member]    
Debt Instrument [Line Items]    
Basis spread on variable rate 1.40%  
Parent Company | Subordinated Notes | Three-month LIBOR | Sky Financial Capital Trust III 2.01% junior subordinated debentures due 2036    
Debt Instrument [Line Items]    
Basis spread on variable rate 1.40%  
Parent Company | Subordinated Notes | Three-month LIBOR | Huntington Capital II Trust Preferred 1.14% junior subordinated debentures due 2028    
Debt Instrument [Line Items]    
Basis spread on variable rate 0.625%  
Parent Company | Subordinated Notes | Three-month LIBOR | Camco Statutory Trust I 2.95% due 2037    
Debt Instrument [Line Items]    
Basis spread on variable rate 1.33%  
Parent Company | Senior Notes | 2.64% Huntington Bancshares Incorporated senior note due 2018    
Debt Instrument [Line Items]    
Long-term borrowings $ 400,544 $ 398,924
Stated rate 2.64%