Employee Benefit Plans (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Dec. 31, 2012	Dec. 31, 2011
Employee Benefit Plans (Textual) [Abstract]
Weighted average discount rate of qualified pension and post-retirement healthcare plans						4.65%
Actual return for qualified pension plan assets	4.10%	7.70%	(7.20%)	(2.50%)
Weighted average annualized expected return on qualified pension plan assets					7.52%
Qualified Pension [Member]
Employee Benefit Plans (Textual) [Abstract]
Employer contribution year-to-date, Pension			19.8
Post-retirement Healthcare [Member]
Employee Benefit Plans (Textual) [Abstract]
Expected employer contribution amount, post-retirement healthcare plan					3.3
Employer contribution year-to-date, Other Postretirement			2.2