Debt Security Held to Maturity - Additional Information (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Schedule Of Held To Maturity Securities [Line Items]
Debt security, held to maturity, at cost	$ 15,000	$ 15,000
Maturity date	Mar. 24, 2019
Debt security bears interest at the rate	The debt security pays interest quarterly at the rate of 4.0% above the three-month London Interbank Offered Rate (“LIBOR”)
Debt security, held to maturity, fair value	$ 14,482	$ 14,307
Debt security, held to maturity, stated interest rate	4.00%