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Basis of Presentation and Summary of Significant Accounting Policies - Additional Information (Detail) $ in Millions	6 Months Ended
	Jun. 30, 2019 USD ($)
Cash And Cash Equivalents And Accounts Payable
New Accounting Pronouncements Or Change In Accounting Principle [Line Items]
Prior period reclassification adjustment	$ 23.0

X

- 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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Balance Type:	na
Period Type:	duration

X

- Definition

The amount of a reclassification adjustment made to prior period financial statement amounts.

+ References

No definition available.

+ Details

Name:	us-gaap_PriorPeriodReclassificationAdjustment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

X

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
Period Type: