Benefit Plans (Details 1) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2011	Dec. 31, 2010	Sep. 30, 2010
Summary of plan assets investments
Fair value of plan assets	$ 472,900	$ 478,479	$ 456,659
Fair value of plan assets, Percentage	100.00%	100.00%	100.00%
Cash [Member]
Summary of plan assets investments
Fair value of plan assets	36	0	0
Fair value of plan assets, Percentage	0.00%	0.00%	0.00%
Huntington funds - equity funds [Member]
Summary of plan assets investments
Fair value of plan assets	264,074	318,155	293,956
Fair value of plan assets, Percentage	56.00%	66.00%	64.00%
Huntington funds - money market [Member]
Summary of plan assets investments
Fair value of plan assets	55	25	204
Fair value of plan assets, Percentage	0.00%	0.00%	0.00%
Huntington funds - fixed income funds [Member]
Summary of plan assets investments
Fair value of plan assets	173,355	133,330	134,523
Fair value of plan assets, Percentage	37.00%	28.00%	30.00%
Huntington common stock [Member]
Summary of plan assets investments
Fair value of plan assets	35,380	26,969	22,344
Fair value of plan assets, Percentage	7.00%	6.00%	5.00%
Other - equity mutual funds [Member]
Summary of plan assets investments
Fair value of plan assets	0	0	4,029
Fair value of plan assets, Percentage	0.00%	0.00%	1.00%
Other [Member]
Summary of plan assets investments
Fair value of plan assets	0	0	0
Fair value of plan assets, Percentage	0.00%	0.00%	0.00%
Corporate Obligations [Member]
Summary of plan assets investments
Fair value of plan assets	0	0	1,097
Fair value of plan assets, Percentage	0.00%	0.00%	0.00%
U.S. Government Agencies [Member]
Summary of plan assets investments
Fair value of plan assets	$ 0	$ 0	$ 506
Fair value of plan assets, Percentage	0.00%	0.00%	0.00%