Acquisitions (Details) (USD $) In Millions, unless otherwise specified	6 Months Ended
	Sep. 30, 2013	Sep. 30, 2012
Business Acquisition [Line Items]
Cash consideration, net of cash acquired	$ 0	$ 4.9
Geofinity Manufacturing of Surrey, British Columbia [Member]
Business Acquisition [Line Items]
Cash consideration, net of cash acquired		4.9
Purchase price allocation resulted in acquired technology		3.5
Purchase price allocation, working capital net assets		0.6
Purchase price allocation, goodwill		0.8
Acquired technology, amortization period		10 years
Radiadores Visconde Ltda [Member]
Business Acquisition [Line Items]
Percentage of interests acquired (in hundredths)		50.00%
Notes payable		2.0
Radiadores Visconde Ltda [Member] | South America [Member]
Business Acquisition [Line Items]
Selling, General and Administrative Expense Increase Decrease		$ 2.0