Expected increase (decrease) in stock option expense.

No definition available.

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- Definition

Share based compensation arrangement by share based payment award options grants in period aggregate grant date fair value.

+ References

No definition available.

+ Details

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- Definition

Net number of share options (or share units) granted during the period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(1)(iv)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

+ Details

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- Definition

Weighted average per share amount at which grantees can acquire shares of common stock by exercise of options.

+ References

No definition available.

+ Details

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

No definition available.

+ Details

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Subsequent Event - Additional Information (Detail) - USD ($)		3 Months Ended	12 Months Ended
	Apr. 28, 2017	Mar. 31, 2017	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Subsequent Event [Line Items]
Options, grant date price		$ 8.52
Scenario, Forecast [Member] \| 2017 [Member]
Subsequent Event [Line Items]
Expected stock option compensation expense increase						$ 1,700,000
Scenario, Forecast [Member] \| 2018 [Member]
Subsequent Event [Line Items]
Expected stock option compensation expense increase					$ 1,600,000
Scenario, Forecast [Member] \| 2019 [Member]
Subsequent Event [Line Items]
Expected stock option compensation expense increase				$ 708,000
Scenario, Forecast [Member] \| 2020 [Member]
Subsequent Event [Line Items]
Expected stock option compensation expense increase			$ 161,000
Subsequent Event [Member] \| Certain Executive Officers and Key Employees [Member]
Subsequent Event [Line Items]
Options, number granted	1,430,000
Options, grant date price	$ 7.52
Options, weighted average fair market value	$ 2.76
Total fair value of options granted	$ 3,900,000