Cash Liability for Performance-Based Units

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- Definition

Minimum age required for meeting directors fees deferred vest criteria.

+ References

No definition available.

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- Definition

Percentage of shares vested in lieu of directors fees at the grant date.

+ References

No definition available.

+ Details

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- Definition

Portion of director fees matched to deferred stock units.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments maximum number of unvested shares.

+ References

No definition available.

+ Details

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- Definition

Share based compensation arrangement by share based payment deferred award vesting period.

+ References

No definition available.

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- Definition

Share-based Compensation Arrangement by Share-based Payment Award, Number of Award Vesting Types

+ References

No definition available.

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- Definition

The amount of expense, net of income tax, recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

+ References

No definition available.

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- Definition

Number of shares issued pursuant to the terms of a deferred compensation arrangement.

+ 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 (l)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting 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)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&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://www.xbrl.org/2003/role/presentationRef
-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=6415400&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.

+ Details

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ 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)(3)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Number of share instruments newly issued under a share-based compensation plan.

+ References

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

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- Definition

Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ 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 (a)(2)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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Stock-Based Compensation - Narrative (Detail) $ in Millions	3 Months Ended		6 Months Ended
Stock-Based Compensation - Narrative (Detail) $ in Millions	Jun. 30, 2017 USD ($) vesting_type	Jun. 30, 2016 USD ($)	Jun. 30, 2017 USD ($) vesting_type yr shares	Jun. 30, 2016 USD ($) shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Number of award vesting types \| vesting_type	2		2
Cash liability for performance-based units \| $	$ 0.0		$ 0.0
Performance Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cancelled in period (in shares)			6,000	0
Options, forfeitures in period (in shares)			8,000	0
Stock-based compensation expense \| $	0.1	$ 0.0	$ 0.3
Stock-based compensation, maximum number of unvested shares (in shares)			336,000
Service Based Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options, forfeitures in period (in shares)			67,000	8,000
Stock-based compensation expense \| $	0.0	0.0	$ 0.1	$ 0.1
Vesting period (in years)			4 years
Expiration period (in years)			8 years
Options issued (in shares)			0	11,000
Deferred Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of shares vested in lieu of directors fees at the grant date			100.00%
Portion of Director fees matched to deferred stock units			25.00%
Vesting period of deferred stock (in years)			1 year
Minimum age required for meeting directors fees deferred vest criteria \| yr			65
Deferred Stock Units \| Director
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Shares issued to non-employee individual (in shares)			45,000	40,000
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Cancelled in period (in shares)			2,000	0
Restricted stock granted in period (in shares)			7,000	0
Deferred stock units, performance-based stock units and restricted stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Stock-based compensation expense \| $	$ 0.4	$ 0.5	$ 0.5	$ 1.1