Benefit Plans (Narratives) (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Apr. 02, 2011
Defined Benefit Plan Disclosure [Line Items]
Pension Plan Transition Contribution	$ 700,000	$ 1,100,000
Postretirement Medical Plans, Description of Change, Limit Employer Medical Contributions, Percent	200.00%
Postretirement Medical Plans, Description of Change, Age Limit for Subsidized Retiree Coverage	65
Deferred Compensation Arrangements, Participating Executive Election to Defer, Percent	1.00%
Defined Benefit Plan, Contributions by Employer, Amount Matched Every One Dollar				0.50
Defined Benefit Plan, Contributions by Employer, Matching Policy Per Dollar				1.00
Defined Benefit Plan, Contributions by Employer, Maximum Limit of Employee Salary, Percent				1.00%
Savings Plan, 401k
Defined Benefit Plan Disclosure [Line Items]
Employer Contributions			1,100,000
FirstMerit | Savings Plan, 401k
Defined Benefit Plan Disclosure [Line Items]
Employer Contributions	$ 7,700,000	$ 4,400,000	$ 600,000