Summary of Significant Accounting Policies (Details) (USD $)	12 Months Ended			339 Months Ended
	Mar. 31, 2014 employees locations	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2014 businesses_acquired employees locations
Significant Accounting Policies [Line Items]
Number of businesses acquired				450
Number of employees	16,000			16,000
Number of locations	1,100			1,100
Interest costs capitalized are immaterial	Capitalized interest recorded for construction in progress during the year ended March 31, 2014 was not material.	Capitalized interest recorded for construction in progress during the year ended March 31, 2013 was not material.	Capitalized interest recorded for construction in progress during the year ended March 31, 2012 was not material.
Asset retirement obligation	$ 19,000,000	$ 18,800,000		$ 19,000,000
Credit Terms Period for Customers, Days	30 days
Distribution costs	850,000,000	841,000,000	797,000,000
Depreciation expense	275,461,000	261,622,000	245,076,000
Transportation equipment [Member]
Significant Accounting Policies [Line Items]
Depreciation expense	32,000,000	30,000,000	27,000,000
Minimum [Member] | Transportation equipment [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Minimum [Member] | Customer relationships [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	7 years
Minimum [Member] | Computer software costs [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	3 years
Maximum [Member] | Transportation equipment [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	15 years
Maximum [Member] | Customer relationships [Member]
Significant Accounting Policies [Line Items]
Finite-Lived Intangible Asset, Useful Life	25 years
Maximum [Member] | Computer software costs [Member]
Significant Accounting Policies [Line Items]
Property, Plant and Equipment, Useful Life	10 years
Selling, Distribution and Administrative Expenses [Member]
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	(15,000,000)
Cost of Products Sold, Excluding Depreciation [Member]
Significant Accounting Policies [Line Items]
Prior period reclassification adjustment	$ 15,000,000