Stock-Based Compensation Plans - Summary of the Activity for the Company's Stock Option Awards (Detail) - $ / shares	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding, Options, Beginning Balance	970,000	1,085,000	1,120,000
Forfeited, Options	(850,000)	(115,000)	(35,000)
Options outstanding, Options, Ending Balance	120,000	970,000	1,085,000
Options exercisable/vested at December 31, 2017	120,000
Forfeited, Exercise Price			$ 3.04
Options Outstanding, Exercise Price, Ending Balance	$ 3.04
Options outstanding, Weighted Average Exercise Price, Beginning Balance	1.81	$ 1.83	1.87
Forfeited, Weighted Average Exercise Price	1.64	2.00	3.04
Options outstanding, Weighted Average Exercise Price, Ending Balance	3.04	1.81	1.83
Options exercisable/vested at December 31, 2017, Weighted Average Exercise Price	3.04
Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Exercise Price, Beginning Balance	1.45	1.45	1.45
Forfeited, Exercise Price	1.45	1.45
Options Outstanding, Exercise Price, Ending Balance		1.45	1.45
Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options Outstanding, Exercise Price, Beginning Balance	3.04	3.04	3.04
Forfeited, Exercise Price	$ 3.04	3.04
Options Outstanding, Exercise Price, Ending Balance		$ 3.04	$ 3.04