v3.19.1

Income Taxes - Additional Information (Detail)	3 Months Ended
	Mar. 31, 2019 USD ($)
Income Tax Contingency [Line Items]
Cumulative effect on retained deficit	$ 0
Unrecognized tax benefits	$ 0
Earliest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2014
Latest Tax Year [Member]
Income Tax Contingency [Line Items]
Open tax year	2018

X

- Definition

Amount of the related income tax effect of a cumulative effect on retained earnings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 250
-SubTopic 10
-Section 50
-Paragraph 9
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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.

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X

- Definition

Tax year that remains open to examination under enacted tax laws, in CCYY format.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 15
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- Definition

Amount of unrecognized tax benefits.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 45
-Paragraph 10B
-URI http://asc.fasb.org/extlink&oid=84176650&loc=SL37586934-109318

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-Section 50
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