Employee Benefit and Bonus Plans - Additional Information (Detail)	12 Months Ended
Dec. 31, 2016 USD ($) Employees	Dec. 31, 2015 USD ($)
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Contributions to the plan	$ 0	$ 0
Executive Performance
Defined Contribution Pension and Other Postretirement Plans Disclosure [Abstract]
Number of employees who are covering executive performance of bonus plan \| Employees	43
Accrued expenses	$ 490,000	$ 460,000

Amount of expense recognized from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments), awarded to key employees or individuals. Excludes amount related to plans that cover generally all employees (for example, but not limited to, qualified pension plans).

No definition available.

Name:	us-gaap_DeferredCompensationArrangementWithIndividualAllocatedShareBasedCompensationExpense
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration