Number of installment payments of employee related payables.

No definition available.

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- Definition

Amount, after tax, of expense for award under share-based payment arrangement.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- 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

+ Details

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued 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

+ Details

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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.

+ Details

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- Details

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- Details

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Stock-Based Compensation Expense (Detail) $ / shares in Units, $ in Millions	1 Months Ended	3 Months Ended		4 Months Ended	6 Months Ended
	Jun. 30, 2018 $ / shares	Jun. 30, 2019 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2019 shares	Jun. 30, 2019 USD ($) Installment	Jun. 30, 2018 USD ($)
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-based compensation expense \| $		$ 1.0	$ 0.5		$ 2.0	$ 0.4
Performance Shares Units \| Officers and Employees
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares granted (in shares) \| shares				3,881
Number of installment payments of employee related payables \| Installment					3
Share-based payment award options grant date fair value (in usd per share) \| $ / shares	$ 31.80