Stockholders' Equity and Noncontrolling Interests - Stock-Based Compensation Information (Detail) - USD ($)	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Stock Appreciation Rights
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Shares	335
Ending balance, Shares	335
Weighted-Average Grant Date Fair Value, Beginning balance	$ 84.41
Weighted-Average Grant Date Fair Value, Ending balance	$ 84.54
Weighted-average contractual remaining life (in years)	3 months 15 days
Exercisable shares	335
Weighted-average exercise price	$ 84.54
Weighted-average exercise price exercisable shares	$ 84.54
Compensation expense (credit)	$ (2,000)	$ (28,000)
Fair value of liability award	$ 13,000		$ 33,000
Restricted Stock Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Shares	10,000
Ending balance, Shares	10,000
Weighted-Average Grant Date Fair Value, Beginning balance	$ 80.05
Weighted-Average Grant Date Fair Value, Ending balance	$ 80.05
Weighted-average contractual remaining life (in years)	3 years 11 months 1 day
Weighted-average exercise price	$ 80.05
Compensation expense (credit)	$ 20,000	201,000
Restricted Stock Units
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Beginning balance, Shares	18,316
Exercised, Shares	(10,816)
Ending balance, Shares	7,500
Weighted-Average Grant Date Fair Value, Beginning balance	$ 111.12
Weighted-Average Grant Date Fair Value, Exercised	103.62
Weighted-Average Grant Date Fair Value, Ending balance	$ 121.93
Weighted-average contractual remaining life (in years)	29 days
Weighted-average exercise price	$ 121.93
Compensation expense (credit)	$ 363,000	$ (211,000)
Fair value of liability award	$ 906,000		$ 2,426,000

Allocated share based compensation expense credit.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options exercisable number.

+ References

No definition available.

+ Details

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the share-based compensation plan for those exercisable shares.

+ References

No definition available.

+ Details

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- Definition

The weighted average fair value at grant date or for equity-based award exercised during the period other than stock option plans.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options fair value of liability component of award.

+ References

No definition available.

+ Details

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the share-based compensation plan.

+ References

No definition available.

+ Details

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

+ References

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- Definition

Weighted average remaining contractual term for equity-based awards excluding options, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

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- Definition

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.

+ References

No definition available.

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- Definition

Number of non-option equity instruments exercised by participants.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(ii)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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