Supplemental Cash Flow Information (Noncash Investing and Financing Activities) (Details) - USD ($) $ in Thousands		3 Months Ended
		Jun. 30, 2015	Jun. 30, 2014
Noncash or Part Noncash Acquisitions [Line Items]
Net cash paid for acquisitions		$ (26,182)	$ (23,463)
Series of Individually Immaterial Business Acquisitions [Member]
Noncash or Part Noncash Acquisitions [Line Items]
Fair value of assets acquired		31,656	35,761
Net cash paid for acquisitions	[1]	(26,182)	(23,463)
Stock issued for acquisition	[2]	0	(4,458)
Liabilities assumed		$ 5,474	$ 7,840

[1] Includes cash paid, net of cash acquired, for current year acquisitions as well as payments for the settlement of holdback liabilities associated with prior year acquisitions.

[2] Represents shares of Airgas, Inc. common stock issued in connection with a single prior year acquisition.