Revenue Recognition - Schedule of Changes in Contract Balances Due to Adoption of New Accounting Standards (Detail) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2019	Dec. 31, 2018
Revenue From Contract With Customer [Abstract]
Contract assets	$ 141,960	$ 126,688
Contract liabilities	(33,435)	(33,494)
Net contract assets (liabilities)	108,525	$ 93,194
Change in contract assets	15,272
Change in contract liabilities	59
Change in net contract assets (liabilities)	$ 15,331
Percentage of change in contract assets	12.10%
Percentage of change in contract liabilities	(0.20%)
Percentage of change in net contract assets (liabilities)	16.50%

Change in contract with customer assets net current.

No definition available.

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- Definition

Change in contract with customer assets liability net current.

+ References

No definition available.

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- Definition

Change in contract with customer liability current.

+ References

No definition available.

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- Definition

Contract with customer assets (liabilities), net current.

+ References

No definition available.

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- Definition

Percentage of change in contract with customer asset net current.

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Percentage of change in contract with customer assets (liabilities) net current.

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Percentage of change in contract with customer liability current.

+ References

No definition available.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 3
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130533-203044

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- Definition

Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130532-203044

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=82913815&loc=SL49130531-203044

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

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