Net Periodic Benefit Cost (Narratives) (Details) (USD $)	6 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Net Periodic Benefit Cost [Abstract]
Defined Benefit Plan Expected Contribution By Employer	$ 10,357,000
Defined Benefit Plan, Curtailments	$ 1,172,000	$ 1,172,000