Fair Value Measurements (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Jun. 30, 2012		Mar. 31, 2012
ASSETS
Cash and cash equivalents	$ 129,906	[1]	$ 134,444	[1]
Restricted cash	4,768		1,962
Marketable securities	4,990	[2]	4,987	[2]
Total	139,664		141,393
LIABILITIES
Contingent consideration related to acquisitions	9,567		6,556
Total	9,567		6,556
Quoted Prices in Active Markets for Identical Assets (Level 1)
ASSETS
Cash and cash equivalents	129,906	[1]	134,444	[1]
Restricted cash	4,768		1,962
Marketable securities	4,990	[2]	4,987	[2]
Total	139,664		141,393
LIABILITIES
Contingent consideration related to acquisitions	0		0
Total	0		0
Significant Other Observable Inputs (Level 2)
ASSETS
Cash and cash equivalents	0	[1]	0	[1]
Restricted cash	0		0
Marketable securities	0	[2]	0	[2]
Total	0		0
LIABILITIES
Contingent consideration related to acquisitions	0		0
Total	0		0
Unobservable Inputs (Level 3)
ASSETS
Cash and cash equivalents	0	[1]	0	[1]
Restricted cash	0		0
Marketable securities	0	[2]	0	[2]
Total	0		0
LIABILITIES
Contingent consideration related to acquisitions	9,567		6,556
Total	$ 9,567		$ 6,556

[1] Cash equivalents consists of money market funds.

[2] Marketable securities consist of fixed-income securities.