Allocated Share Based Compensation Expense Benefit

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- Definition

Performance Period for Performance RSUs

+ References

No definition available.

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- Definition

Share Based Compensation Arrangement By Share Based Payment Award Equity Instruments Other Than Options Forfeited In Period Fair Value

+ References

No definition available.

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- Definition

Stock Based Compensation [Line Items]

+ References

No definition available.

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- Definition

Time vested restricted stock units forfeiture restrictions lapsation percentage.

+ References

No definition available.

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- Definition

Time vested restricted stock units forfeiture restrictions lapsation period.

+ References

No definition available.

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- Definition

Aggregate cash paid by the entity during the period to settle equity instruments granted under equity-based payment arrangements.

+ 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 (k)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Unrecognized cost of unvested share-based awards, other than options, awarded to employees as compensation.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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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

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

Fair value of share-based awards for which the grantee gained the right by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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- Definition

The maximum number of shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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-Publisher FASB
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- Definition

The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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-Publisher FASB
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-Section 50
-Paragraph 2
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- Definition

Price of a single share of a number of saleable stocks of a company.

+ References

No definition available.

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Stock-based Compensation - Additional Information (Detail) - USD ($)		12 Months Ended
	Feb. 20, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Stock Based Compensation [Line Items]
Compensation expense related to incentive plans		$ 6,100,000	$ 4,400,000	$ (100,000)
Non-Voting Time-Vested Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Weighted average grant date fair value (in USD per share)		$ 12.55	$ 11.42
Aggregate value of vested shares		$ 300,000	$ 1,500,000
Recognized / Unrecognized compensation cost		$ 5,900,000
Weighted average period		1 year 10 months 17 days
Aggregate value of forfeited shares			$ 400,000
Non-Voting Time-Vested Restricted Stock Units [Member] \| Maximum [Member]
Stock Based Compensation [Line Items]
Aggregate value of forfeited shares		$ 77,000
Non-Voting Performance Based Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Weighted average grant date fair value (in USD per share)		$ 12.54
Aggregate value of vested shares		$ 0
Recognized / Unrecognized compensation cost		4,900,000
Aggregate value of forfeited shares		$ 2,100,000
2012 Long - Term Incentive Plan [Member] \| Amended and Restated 2015 Long Term Incentive Plan [Member]
Stock Based Compensation [Line Items]
Shares available for issuance (shares)		1,149,175
Forfeiture restrictions percentage		100.00%
Vesting period of employees		3 years
2012 Long - Term Incentive Plan [Member] \| Amended and Restated 2015 Long Term Incentive Plan [Member] \| Non-Voting Common Stock [Member]
Stock Based Compensation [Line Items]
Common stock authorized to issue (shares)		3,500,000
Subsequent Event [Member] \| Non-Voting Performance Based Restricted Stock Units [Member]
Stock Based Compensation [Line Items]
Performance period for performance RSUs	2 years
Closing market price on effective date for RSU settlement (in USD per share)	$ 2.21
Vested performance RSUs settled with cash	$ 800,000