Equity-Based Compensation, Profit Sharing and Deferred Compensation Plans - Summary of Equity-Based Compensation Plans with Grants Outstanding (Textual) (Detail) - $ / shares	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized	60,000,000	60,000,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period, Weighted Average Grant Date Fair Value	$ 3,015.83
RSUs \| Option Grant Solely Contingent upon Continued Employment or Continued Service as a Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of options vesting rights	50.00%
Restricted share units vesting period or option vesting period	2 years
Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding	1,049,000	916,000
Options \| Option Grant Solely Contingent upon Continued Employment or Continued Service as a Director
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of options vesting rights	50.00%
Restricted share units vesting period or option vesting period	2 years
Options \| Option Grant Contingent upon Continued Employment or Service as a Director and Achievement of Performance Metric
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Percentage of options vesting rights	25.00%
Restricted share units vesting period or option vesting period	4 years
2010 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	700,000
Shares Available to Issue	26,000
2010 Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	240,000
Restricted share units outstanding	21,000	10,000
Common stock, shares authorized	22,000
2010 Plan \| Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Options outstanding	139,000
2014 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	950,000
Shares Available to Issue	102,000
2014 Plan \| Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Performance metric period	3 years
2018 Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares authorized	275,000
Shares Available to Issue	129,000
2018 Plan \| RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, shares authorized	40,000

Performance metric based on return on capital performance period.

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Share-Based Compensation Arrangement By Share Based Payment Award, Equity Instruments Other Than Options Outstanding, Number

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- Definition

The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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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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- Definition

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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
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-Paragraph 2
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- Definition

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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- Definition

Number of options outstanding, including both vested and non-vested options.

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-Topic 718
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- Definition

Percentage of vesting of share-based compensation awards.

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