Subsequent Events - Additional Information (Detail) (USD $) In Millions, unless otherwise specified				1 Months Ended
	Mar. 22, 2013	Mar. 18, 2013	Apr. 26, 2013 Second capital contribution	Apr. 12, 2013 Letter of Credit
Subsequent Event [Line Items]
Letter of credit issued				$ 0.2
Expiration Date				April 15, 2014
Capital contribution made by company	$ 3.15	$ 3.15	$ 1.85