Annual report pursuant to Section 13 and 15(d)

Benefit Plans (Details Textuals)

v2.4.0.6
Benefit Plans (Details Textuals) (USD $)
 12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Dec. 31, 2010
Benefit Plans (Textuals) [Abstract]        
Contribution to plan   $ 75,000,000    
Employees retirement age for health care and life insurance benefits under unfunded defined benefit post-retirement plan   55    
Employees vesting service under defined benefit post-retirement plan, minimum   10 years    
Life insurance coverage, maximum   50,000    
Contributions Received For Retiree Medical Program   2,800,000    
Defined Benefit Plan, Accumulated Benefit Obligation   775,200,000 651,300,000  
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Asset        
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Projected Benefit Obligation   150,200,000    
Defined Benefit Plan, Pension Plans with Accumulated Benefit Obligations in Excess of Plan Assets, Aggregate Accumulated Benefit Obligation   141,600,000    
Defined Benefit Plan Expenses   1,100,000 800,000 1,000,000
Estimated Net Periodic Pension Cost In Next Fiscal Year   42,700,000    
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]        
Pension and Other Postretirement Defined Benefit Plans, Liabilities   35,400,000 26,900,000  
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]        
Defined Benefit Plan, Amortization of Net Transition Asset (Obligation)   0    
Defined Benefit Plan, Amortization of Net Prior Service Cost (Credit)   7,100,000    
Defined Benefit Plan, Amortization of Net Gains (Losses)   38,500,000    
Average duration of plan assets investment in bonds, years   12 years 0 months    
Base pay contributed to the plan up to first 4% up to first 3%    
Attributes of employees contribution to defined contribution plan   Half of the employee contribution was matched on the 4th and 5th percent of base pay contributed to the Plan.    
Effect of One-Percentage Point Change in Assumed Health Care Cost Trend Rates [Abstract]        
Effect of One Percentage Point Increase on Service and Interest Cost Components   10,000    
Effect of One Percentage Point Decrease on Service and Interest Cost Components   10,000    
Effect of One Percentage Point Increase on Accumulated Postretirement Benefit Obligation   10,000    
Effect of One Percentage Point Decrease on Accumulated Postretirement Benefit Obligation   20,000    
Defined Benefit Plan, Year that Rate Reaches Ultimate Trend Rate   2028    
Defined Benefit Plan, Ultimate Health Care Cost Trend Rate   4.50%    
Defined Benefit Plan, Description of Direction and Pattern of Change for Assumed Health Care Cost Trend Rate   These rates are assumed to decrease gradually    
Estimated Net Periodic Post Retirement Benefit Cost In Next Fiscal Year   0    
Estimated Life Of Benefit Obligations   14 years    
Fair value of plan assets, Percentage   100.00% 100.00%  
Post Retirement Benefits [Member]
        
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]        
Defined Benefit Plan, Estimated Future Employer Contributions in Next Fiscal Year   $ 3,100,000    
Post 65 [Member]
        
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]        
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year   8.20%    
Equity Securities [Member]
        
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]        
Defined Benefit Plan, Actual Plan Asset Allocations   55.00%    
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum   20.00%    
Defined Benefit Plan, Target Plan Assets Allocation Range Maximum   50.00%    
Covered Bonds [Member]
        
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]        
Defined Benefit Plan, Actual Plan Asset Allocations   44.00%    
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum   50.00%    
Defined Benefit Plan, Target Plan Assets Allocation Range Maximum   80.00%    
Covered Bonds [Member] | Pre 65 [Member]
        
Defined Benefit Plan, Assumed Health Care Cost Trend Rates [Abstract]        
Defined Benefit Plan, Health Care Cost Trend Rate Assumed for Next Fiscal Year   7.70%    
Cash and Cash Equivalents [Member]
        
Pension and Other Postretirement Benefit Plans, Amounts that Will be Amortized from Accumulated Other Comprehensive Income (Loss) in Next Fiscal Year [Abstract]        
Defined Benefit Plan, Actual Plan Asset Allocations   1.00%