Cash, Cash Equivalents and Investments - Schedule of Company's Investments Measured at Fair Value (Detail) (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014
Cash And Short Term Investments [Line Items]
Amortized Cost	$ 77,507
Total Fair Value	77,517
Corporate Bonds [Member]
Cash And Short Term Investments [Line Items]
Amortized Cost	14,781
Total Fair Value	14,767
State and Municipal Obligations [Member]
Cash And Short Term Investments [Line Items]
Amortized Cost	15,213
Total Fair Value	15,237
Cash [Member]
Cash And Short Term Investments [Line Items]
Amortized Cost	40,827
Total Fair Value	40,827
Money Market Funds [Member]
Cash And Short Term Investments [Line Items]
Amortized Cost	4,070
Total Fair Value	4,070
Certificates of Deposit [Member]
Cash And Short Term Investments [Line Items]
Amortized Cost	2,616
Total Fair Value	2,616
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value	59,664
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Corporate Bonds [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value	14,767
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | State and Municipal Obligations [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Cash [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value	40,827
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Money Market Funds [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value	4,070
Quoted Prices in Active Markets for Identical Assets (Level 1) [Member] | Certificates of Deposit [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Other Observable Inputs (Level 2) [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value	17,853
Significant Other Observable Inputs (Level 2) [Member] | Corporate Bonds [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Other Observable Inputs (Level 2) [Member] | State and Municipal Obligations [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value	15,237
Significant Other Observable Inputs (Level 2) [Member] | Cash [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Other Observable Inputs (Level 2) [Member] | Money Market Funds [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Other Observable Inputs (Level 2) [Member] | Certificates of Deposit [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value	2,616
Significant Unobservable Inputs (Level 3) [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Unobservable Inputs (Level 3) [Member] | Corporate Bonds [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Unobservable Inputs (Level 3) [Member] | State and Municipal Obligations [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Unobservable Inputs (Level 3) [Member] | Cash [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Unobservable Inputs (Level 3) [Member] | Money Market Funds [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value
Significant Unobservable Inputs (Level 3) [Member] | Certificates of Deposit [Member]
Cash And Short Term Investments [Line Items]
Total Fair Value