Fair Value Measurements (Details) (Fair Value, Measurements, Recurring [Member], USD $) In Thousands, unless otherwise specified	Sep. 30, 2014		Mar. 31, 2014
ASSETS
Cash and cash equivalents	$ 114,980	[1]	$ 103,145	[1]
Restricted cash and cash equivalents	2,445		4,351
Marketable securities	8,536	[2]	10,656	[2]
Total	125,961		118,152
LIABILITIES
Fair value of contingent consideration	15,231		14,913
Total	15,231		14,913
Quoted Prices in Active Markets for Identical Assets (Level 1)
ASSETS
Cash and cash equivalents	114,980	[1]	103,145	[1]
Restricted cash and cash equivalents	2,445		4,351
Marketable securities	8,536	[2]	10,656	[2]
Total	125,961		118,152
LIABILITIES
Fair value of contingent consideration	0		0
Total	0		0
Significant Other Observable Inputs (Level 2)
ASSETS
Cash and cash equivalents	0	[1]	0	[1]
Restricted cash and cash equivalents	0		0
Marketable securities	0	[2]	0	[2]
Total	0		0
LIABILITIES
Fair value of contingent consideration	0		0
Total	0		0
Unobservable Inputs (Level 3)
ASSETS
Cash and cash equivalents	0	[1]	0	[1]
Restricted cash and cash equivalents	0		0
Marketable securities	0	[2]	0	[2]
Total	0		0
LIABILITIES
Fair value of contingent consideration	15,231		14,913
Total	$ 15,231		$ 14,913

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

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