Share-Based Payments - Summary of Outstanding Restricted Stock Units (Detail) - Restricted Stock Units - Equity Incentive Plan	3 Months Ended
Mar. 31, 2020 shares
2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Awarded (in shares)	2,870
Service period in years	5 years
2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Awarded (in shares)	152,048
Service period in years	3 years
2020
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Units Awarded (in shares)	120,824
Service period in years	3 years

Estimated period over which an employee is required to provide service in exchange for the equity-based payment award, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=116856206&loc=d3e5070-113901

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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.

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