Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Line Items]
Federal income tax at statutory rate	35.00%	35.00%	35.00%	35.00%
Percentage of tax position will realized or sustained upon examination		50.00%
Net operating loss carryovers	$ 5.4	$ 5.4
Net operating loss carryovers expire period		2023 through 2031
Minimum
Income Taxes [Line Items]
Percentage of tax position will realized or sustained upon examination		50.00%