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

AVAILABLE-FOR-SALE AND OTHER SECURITIES - Schedule of Amortized Cost, Fair Value, and Gross Unrealized Gains and Losses (Details)

AVAILABLE-FOR-SALE AND OTHER SECURITIES - Schedule of Amortized Cost, Fair Value, and Gross Unrealized Gains and Losses (Details) - USD ($) $ in Thousands	Jun. 30, 2016	Dec. 31, 2015
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 9,522,960	$ 8,770,923
Unrealized Gross Gains	193,331	88,169
Unrealized Gross Losses	(63,253)	(83,651)
Fair Value	9,653,038	8,775,441
U.S. Treasury
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	7,266	5,457
Unrealized Gross Gains	54	15
Unrealized Gross Losses	0	0
Fair Value	7,320	5,472
Federal agencies: Mortgage-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,121,788	4,505,318
Unrealized Gross Gains	96,433	30,078
Unrealized Gross Losses	(429)	(13,708)
Fair Value	5,217,792	4,521,688
Federal agencies, Other agencies
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	83,043	115,076
Unrealized Gross Gains	2,950	888
Unrealized Gross Losses	0	(51)
Fair Value	85,993	115,913
Total U.S. Treasury, Federal agency securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	5,212,097	4,625,851
Unrealized Gross Gains	99,437	30,981
Unrealized Gross Losses	(429)	(13,759)
Fair Value	5,311,105	4,643,073
Municipal securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	2,534,245	2,431,943
Unrealized Gross Gains	75,326	51,558
Unrealized Gross Losses	(27,944)	(27,105)
Fair Value	2,581,627	2,456,396
Asset-backed securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	920,033	901,059
Unrealized Gross Gains	5,408	535
Unrealized Gross Losses	(34,869)	(40,181)
Fair Value	890,572	861,413
Corporate debt
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	507,292	464,207
Unrealized Gross Gains	12,720	4,824
Unrealized Gross Losses	(8)	(2,554)
Fair Value	520,004	466,477
Other securities
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	349,293	347,863
Unrealized Gross Gains	440	271
Unrealized Gross Losses	(3)	(52)
Fair Value	$ 349,730	$ 348,082