Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The total recognized tax benefit related to compensation cost for equity-based payment arrangements recognized in income during the period.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Number of share instruments newly issued under a share-based compensation plan.

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Amount of capitalized and expensed compensation cost from equity-based compensation arrangements.

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Number of non-vested options forfeited.

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Stock-based Compensation - Summary of Information with Respect to Stock-Based Compensation (Detail) - USD ($)			3 Months Ended		9 Months Ended
	May 24, 2018	May 22, 2014	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
General and administrative expenses			$ 800,000	$ 400,000	$ 1,200,000	$ 400,000
Income tax benefit related to stock-based compensation included in net income			870,000	771	2,219,000	1,792
General and Administrative Expense [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Salaries and employee benefits (1)			$ 0	$ 0	$ 460,000	$ 563
Two Thousand Twelve Program [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized							1,300,000
Share-based Compensation Arrangement by Share-based Payment Award, Number of Additional Shares Authorized	850,000	700,000
Share-based Compensation Arrangement by Share-based Payment Award, Shares Issued in Period					2,495,928
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Available for Grant			1,032,494		1,032,494
Share-based Compensation Arrangement by Share-based Payment Award, Options, Nonvested Options Forfeited, Number of Shares					678,422