Fair Value Measurement (Details) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Mar. 31, 2013
Cash equivalents:
Money market funds	$ 14,378	$ 14,376
Short-term investments:
Mutual funds	1,899	1,964
Total	16,277	16,340
Quoted Prices in Active Markets for Identical Assets (Level 1)
Cash equivalents:
Money market funds	14,378	14,376
Short-term investments:
Mutual funds	1,899	1,964
Total	16,277	16,340
Other Observable Inputs (Level 2)
Cash equivalents:
Money market funds	0	0
Short-term investments:
Mutual funds	0	0
Total	0	0
Significant Unobservable Inputs (Level 3)
Cash equivalents:
Money market funds	0	0
Short-term investments:
Mutual funds	0	0
Total	$ 0	$ 0