Acquisitions and Divestitures (Summary Of Fair Values Of The Assets Acquired And Liabilities Assumed) (Details) (USD $) In Thousands, unless otherwise specified				12 Months Ended
Mar. 31, 2014	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014 FY14 Acquisitions [Member]	Mar. 31, 2013 FY13 Acquisitions [Member]	Mar. 31, 2012 FY12 Acquisitions [Member]	Mar. 31, 2014 Distribution Business Segment [Member]	Mar. 31, 2013 Distribution Business Segment [Member]	Mar. 31, 2012 Distribution Business Segment [Member]	Mar. 31, 2014 Distribution Business Segment [Member] FY14 Acquisitions [Member]	Mar. 31, 2013 Distribution Business Segment [Member] FY13 Acquisitions [Member]	Mar. 31, 2012 Distribution Business Segment [Member] FY12 Acquisitions [Member]	Mar. 31, 2014 All Other Operations Business Segment [Member]	Mar. 31, 2013 All Other Operations Business Segment [Member]	Mar. 31, 2012 All Other Operations Business Segment [Member]	Mar. 31, 2014 All Other Operations Business Segment [Member] FY14 Acquisitions [Member]	Mar. 31, 2013 All Other Operations Business Segment [Member] FY13 Acquisitions [Member]	Mar. 31, 2012 All Other Operations Business Segment [Member] FY12 Acquisitions [Member]
Business Acquisition [Line Items]
Net Cash Paid For Acquired Businesses And Settlement Of Holdback Liabilities And Contingent Consideration				$ 205,000	$ 97,521	$ 160,115
Current assets, net				14,640	15,175	22,407				14,631	14,627	17,390				9	548	5,017
Plant and equipment				48,173	25,209	69,992				48,919	24,191	54,505				(746)	1,018	15,487
Goodwill	1,289,896	1,195,613	1,163,803	95,410	34,205	49,902	1,092,728	998,128	969,394	95,626	31,104	42,073	197,168	197,485	194,409	(216)	3,101	7,829
Other intangible assets				60,190	40,813	41,716				60,190	38,658	34,486				0	2,155	7,230
Current liabilities				(4,722)	(13,124)	(14,412)				(6,088)	(10,990)	(13,386)				1,366	(2,134)	(1,026)
Non-current liabilities				(8,321)	(4,757)	(9,490)				(8,321)	(4,035)	(5,937)				0	(722)	(3,553)
Net assets acquired				$ 205,370	$ 97,521	$ 160,115				$ 204,957	$ 93,555	$ 129,131				$ 413	$ 3,966	$ 30,984

Net Cash Paid For Acquired Businesses And Settlement Of Holdback Liabilities And Contingent Consideration

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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Amount of liabilities due within one year or within the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of identifiable intangible assets recognized as of the acquisition date.

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Amount of liabilities due after one year or the normal operating cycle, if longer, assumed at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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Amount recognized for assets, including goodwill, in excess of (less than) the aggregate liabilities assumed.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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