Fair Value - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2014
Minimum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Period of Investment	2 years
Maximum [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Period of Investment	5 years