Huntington Bancshares Incorporated Quarterly report pursuant to Section 13 or 15(d)

AVAILABLE-FOR-SALE AND OTHER SECURITIES - Collateralized Debt Obligation (Details) - USD ($) $ in Thousands	Sep. 30, 2017	Dec. 31, 2016
Schedule of Available-for-sale Securities [Line Items]
Unrealized Gross Losses	$ (203,017)	$ (261,644)
Pooled Trust Preferred
Schedule of Available-for-sale Securities [Line Items]
Par Value	61,009	137,197
Amortized Cost	35,397	101,210
Fair Value	24,127	76,003
Unrealized Gross Losses	(11,270)	$ (25,207)
Pooled Trust Preferred \| MM Comm III
Schedule of Available-for-sale Securities [Line Items]
Par Value	4,509
Amortized Cost	4,308
Fair Value	3,641
Unrealized Gross Losses	$ (667)
Actual Deferrals and Defaults as Percent of Original Collateral	5.00%
Expected Defaults as Percent of Remaining Performing Collateral	7.00%
Excess Subordination	34.00%
Pooled Trust Preferred \| Reg Diversified
Schedule of Available-for-sale Securities [Line Items]
Par Value	$ 25,500
Amortized Cost	100
Fair Value	510
Unrealized Gross Losses	$ (410)
Actual Deferrals and Defaults as Percent of Original Collateral	0.00%
Expected Defaults as Percent of Remaining Performing Collateral	0.00%
Excess Subordination	0.00%
Pooled Trust Preferred \| Tropic III
Schedule of Available-for-sale Securities [Line Items]
Par Value	$ 31,000
Amortized Cost	30,989
Fair Value	19,976
Unrealized Gross Losses	$ (11,013)
Actual Deferrals and Defaults as Percent of Original Collateral	16.00%
Expected Defaults as Percent of Remaining Performing Collateral	6.00%
Excess Subordination	41.00%