Fair Value Measurements (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Jun. 30, 2014		Mar. 31, 2014
ASSETS
Cash and cash equivalents	$ 107,748	[1]	$ 103,145	[1]
Restricted cash	2,605		4,351
Marketable securities	8,687	[2]	10,656	[2]
Total	119,040		118,152
LIABILITIES
Contingent consideration related to acquisitions	15,517		14,913
Total	15,517		14,913
Quoted Prices in Active Markets for Identical Assets (Level 1)
ASSETS
Cash and cash equivalents	107,748	[1]	103,145	[1]
Restricted cash	2,605		4,351
Marketable securities	8,687	[2]	10,656	[2]
Total	119,040		118,152
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	15,517		14,913
Total	$ 15,517		$ 14,913

[1] Cash and cash equivalents consists of money market funds.

[2] Marketable securities consist of fixed-income securities, including certificates of deposit and municipal securities.