Annual report pursuant to Section 13 and 15(d)

Benefit Plans (Details)

v2.4.0.6
Benefit Plans (Details) (USD $)
 12 Months Ended
Dec. 31, 2011
Dec. 31, 2010
Dec. 31, 2009
Change in Fair Value of Plan Assets      
Defined Benefit Plan, Fair Value of Plan Assets, Ending Balance $ 538,970,000 $ 478,479,000  
Pension Benefits [Member]
      
Components of net periodic benefit expense      
Service cost 21,650,000 20,205,000 23,692,000
Interest cost 30,073,000 28,869,000 28,036,000
Expected return on plan assets (43,290,000) (42,113,000) (41,960,000)
Amortization of transition asset (5,000) 5,000 6,000
Amortization of prior service cost (5,767,000) (5,766,000) (553,000)
Amortization of gains (losses) 23,494,000 14,989,000 8,689,000
Curtailments 0 0 0
Settlements 5,483,000 9,694,000 6,213,000
Benefit expense 31,638,000 25,883,000 24,123,000
Change in Benefit Obligation [Roll Forward]      
Defined Benefit Plan, Benefit Obligation, Beginning Balance 577,770,000 504,859,000  
Service cost 21,650,000 20,205,000 23,692,000
Interest cost 30,073,000 28,869,000 28,036,000
Benefits Paid (12,285,000) (11,367,000)  
Settlements (10,408,000) (20,582,000)  
Business Combinations and Acquisitions 0 896,000  
Plan Amendments 0 0  
Curtailments 0 0  
Gross Prescription Drug Subsidy Receipts Received 0 0  
Actuarial Net (Gains) Losses 49,539,000 54,890,000  
Period Increase (Decrease) 78,569,000 72,911,000  
Defined Benefit Plan, Benefit Obligation, Ending Balance 656,339,000 577,770,000 504,859,000
Weighted Average Assumptions Used in Calculating Benefit Obligation      
Discount Rate 4.57% 5.35%  
Rate of Compensation Increase 4.50% 4.50%  
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost      
Discount Rate 5.35% 5.88%  
Long-term Return on Assets 8.00% 8.00%  
Compensation Increase 4.50% 4.50%  
Change in Fair Value of Plan Assets      
Defined Benefit Plan, Fair Value of Plan Assets, Beginning Balance 478,479,000 454,114,000  
Actual Return on Plan Assets (6,593,000) 55,583,000  
Contributions by Employer 90,000,000 79,000  
Settlements, Plan Assets (10,631,000) (20,911,000)  
Business Combinations and Acquisitions 0 981,000  
Benefits Paid (12,285,000) (11,367,000)  
Period Increase (Decrease) 60,491,000 24,365,000  
Defined Benefit Plan, Fair Value of Plan Assets, Ending Balance 538,970,000 478,479,000 454,114,000
Estimated Future Benefit Payments      
Expected Future Benefit Payments in Year One 34,124,000    
Expected Future Benefit Payments in Year Two 36,006,000    
Expected Future Benefit Payments in Year Three 36,874,000    
Expected Future Benefit Payments in Year Four 38,573,000    
Expected Future Benefit Payments in Year Five 40,533,000    
Expected Future Benefit Payments in Five Fiscal Years Thereafter 225,480,000    
Defined Benefit Plan, Information about Plan Assets [Abstract]      
Shares of Huntington Stock 7,309,986 [1] 3,919,986 [1]  
Dividends on Huntington Stock 400,000 200,000  
Post Retirement Benefits [Member]
      
Components of net periodic benefit expense      
Service cost 0 0 1,550,000
Interest cost 1,618,000 1,731,000 3,274,000
Expected return on plan assets 0 0 0
Amortization of transition asset 0 0 920,000
Amortization of prior service cost (1,354,000) (1,353,000) 91,000
Amortization of gains (losses) (423,000) (699,000) (888,000)
Curtailments 0 0 (527,000)
Settlements 0 0 0
Benefit expense (159,000) (321,000) 4,420,000
Change in Benefit Obligation [Roll Forward]      
Defined Benefit Plan, Benefit Obligation, Beginning Balance 34,241,000 33,173,000  
Service cost 0 0 1,550,000
Interest cost 1,618,000 1,731,000 3,274,000
Benefits Paid (4,895,000) (5,103,000)  
Settlements 0 0  
Business Combinations and Acquisitions 0 0  
Plan Amendments 0 0  
Curtailments 0 0  
Gross Prescription Drug Subsidy Receipts Received 670,000 753,000  
Actuarial Net (Gains) Losses 1,217,000 3,687,000  
Period Increase (Decrease) (1,390,000) 1,068,000  
Defined Benefit Plan, Benefit Obligation, Ending Balance 32,851,000 34,241,000 33,173,000
Weighted Average Assumptions Used in Calculating Benefit Obligation      
Discount Rate 4.34% 5.00%  
Weighted Average Assumptions Used in Calculating Net Periodic Benefit Cost      
Discount Rate 5.00% 5.54%  
Change in Fair Value of Plan Assets      
Benefits Paid (4,895,000) (5,103,000)  
Estimated Future Benefit Payments      
Expected Future Benefit Payments in Year One   4,297,000  
Expected Future Benefit Payments in Year Two   4,110,000  
Expected Future Benefit Payments in Year Three   3,923,000  
Expected Future Benefit Payments in Year Four   3,759,000  
Expected Future Benefit Payments in Year Five   3,588,000  
Expected Future Benefit Payments in Five Fiscal Years Thereafter   15,694,000  
Defined Contribution Pension [Member]
      
Defined Benefit Plan, Information about Plan Assets [Abstract]      
Market Value-Amount of Huntington common stock 82,600,000 102,700,000  
Shares of Huntington Stock 15,051,291 14,945,498  
Dividends on Huntington Stock $ 1,100,000 $ 600,000  
[1] The Plan has acquired and held Huntington common stock in compliance at all times with Section 407 of the Employee Retirement Income Security Act of 1978.