Segment and Enterprise Wide Disclosures - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended					3 Months Ended
	Jun. 30, 2012 Segment	Jun. 30, 2012 UNITED STATES	Mar. 31, 2012 UNITED STATES	Jun. 30, 2012 Europe	Mar. 31, 2012 Europe	Jun. 30, 2012 International	Jun. 30, 2011 International
Segment Reporting Information [Line Items]
Number of business segments	1
Percentage of total consolidated assets		70.00%	68.00%
Goodwill and intangibles				$ 34.7	$ 37.0
Percentage of total consolidated assets, excluding goodwill and intangibles				7.00%	8.00%
Percentage of total product revenue						5.00%	7.00%