Goodwill And Other Intangible Assets (Changes In Goodwill) (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Goodwill [Roll Forward]
Goodwill at period start date	$ 1,163,803		$ 1,117,336
Acquisitions	34,205	[1]	49,902	[1]
Other adjustments, including foreign currency translation	(2,395)		(3,435)
Goodwill at period end date	1,195,613		1,163,803
Distribution Business Segment [Member]
Goodwill [Roll Forward]
Goodwill at period start date	969,394		930,718
Acquisitions	31,104	[1]	42,073	[1]
Other adjustments, including foreign currency translation	(2,370)		(3,397)
Goodwill at period end date	998,128		969,394
All Other Operations Business Segment [Member]
Goodwill [Roll Forward]
Goodwill at period start date	194,409		186,618
Acquisitions	3,101	[1]	7,829	[1]
Other adjustments, including foreign currency translation	(25)		(38)
Goodwill at period end date	$ 197,485		$ 194,409

[1] Includes acquisitions completed during the respective year and adjustments made to prior year acquisitions.