Marketable Investments - Summary of Maturity Periods of the Marketable Securities (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Schedule of Available-for-sale Securities [Line Items]
FY 2014	$ 9,079
FY2015	44,031
FY2016	18,272
Thereafter	9,642
Total	81,024	81,013
State and Municipal Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
FY 2014	2,201
FY2015	2,005
Total	4,206	6,814
Federal Agency and Corporate Obligations [Member]
Schedule of Available-for-sale Securities [Line Items]
FY 2014	6,878
FY2015	42,026
FY2016	18,272
Thereafter	9,642
Total	$ 76,818	$ 74,199