The number of minor businesses acquired by the entity during the period.

No definition available.

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- Definition

The capitalized costs incurred during the period (excluded from amortization) to purchase, lease or otherwise acquire an unproved property, including costs of lease bonuses and options to purchase or lease properties, the portion of costs applicable to minerals when land including mineral rights is purchased in fee, brokers' fees, recording fees, legal costs, and other costs incurred in acquiring properties.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 932
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.4-10(c)(7)(ii))
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-Subparagraph (SX 210.4-10(c)(3)(ii)(A))
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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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-Name Accounting Standards Codification
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-SubTopic 10
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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.

+ Details

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- Definition

Percentage of voting equity interests acquired at the acquisition date in the business combination.

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-Name Accounting Standards Codification
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-SubTopic 10
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-Paragraph 2
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- Definition

The amount of goodwill arising from a business combination that is expected to be deductible for tax purposes.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (d)
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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to items of consideration transferred in connection with a business combination for which the initial accounting was incomplete.

+ References

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-Publisher FASB
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-SubTopic 20
-Section 50
-Paragraph 4A
-Subparagraph (c)
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- Definition

This element represents the amount of any measurement period adjustment (as defined) realized during the reporting period to financial liabilities assumed in connection with a business combination for which the initial accounting was incomplete.

+ References

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Balance Type:	credit
Period Type:	duration

- Definition

Amount of increase (decrease) of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
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- Definition

Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

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-Publisher FASB
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-Subparagraph (a)
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- Definition

The number of businesses acquired by the entity during the period.

+ References

No definition available.

+ Details

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- Details

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Business Combinations - Additional Information (Detail) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Sep. 30, 2018 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2018 USD ($) Business	Sep. 30, 2017 USD ($) Business	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Number of businesses acquired \| Business			8	7
Percentage of voting equity interests acquired	100.00%	100.00%	100.00%	100.00%
Number of minor businesses acquired \| Business			1	2
Goodwill acquired expected to be tax deductible	$ 12,400		$ 12,400
Amortization of intangibles	5,228	$ 6,824	19,678	$ 19,790
Income tax expense (benefit)	5,358	5,721	12,762	15,502
Administrative [Member]
Business Acquisition [Line Items]
Acquisition-related costs	700	900	1,900	2,300
Alpha [Member]
Business Acquisition [Line Items]
Increase in goodwill					$ 2,100
Combined Business Acquisitions [Member]
Business Acquisition [Line Items]
Amortization of intangibles	200	900	1,200	3,200
Income tax expense (benefit)	$ 200	$ 500	700	$ 2,000
Columbia [Member]
Business Acquisition [Line Items]
Increase in goodwill			500
Increase in seller obligations			400
Increase in purchase price			$ 600