Long-Term Debt - Notes Payable to BMI - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2013	Jan. 31, 2013	Dec. 31, 2012
Debt Instrument [Line Items]
Cash Collateral	$ 33,300,000		$ 20,900,000
BMI | Bank note payable
Debt Instrument [Line Items]
Debt instrument	11,200,000	11,900,000
Cash Collateral		750,000
Periodic principal payments	$ 100,000
Loans maturity period	Jan. 31, 2025
Frequency of debt instrument payment	Monthly
Interest rate terms	note bears interest at a variable rate equal to the prime rate with a floor of 3.25% and a ceiling of 9.0%.
Debt instrument, Interest rate at period end	3.25%
BMI | Bank note payable | Minimum
Debt Instrument [Line Items]
Percentage of average interest rate during period	3.25%
BMI | Bank note payable | Maximum
Debt Instrument [Line Items]
Percentage of average interest rate during period	9.00%