Contingently issuable shares.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options granted and deferred in period.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options granted and issued excluding deferred in period.

+ References

No definition available.

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- Definition

Share based compensation arrangement by share based payment award equity instruments other than options withheld for taxes in period.

+ References

No definition available.

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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://fasb.org/us-gaap/role/ref/legacyRef
-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=109197908&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
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

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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

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- Definition

Number of additional shares authorized for issuance under an established share-based compensation plan.

+ References

No definition available.

+ Details

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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).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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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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-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

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Stockholders' Equity (Deficit) - Summary of Changes in Common Shares Available for Awards under Omnibus Incentive Plan and Predecessor Plans (Detail) - shares	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	May 22, 2014
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares forfeited (in shares)	(86,518)	(184,235)	(89,699)
Omnibus Incentive Plan and 2005 Contingent Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Number of shares available, beginning of year	3,668,954	5,385,870	7,694,739
Restricted stock shares issued for new awards	(571,438)	(480,283)	(481,834)
Shares withheld for taxes	94,624	101,767	0
Number of shares available, end of year	4,489,347	3,668,954	5,385,870
2014 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Newly Registered Shares under Omnibus Incentive Plan (in shares)	2,199,114	0	0
Restricted stock shares issued for new awards	(1,478)
2012 President and COO Four-year Incentive Compensation
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares issued for new awards	0	0	(325,000)
2014 Special PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares issued for new awards	(658,783)	(749,653)	0
2015 Three-year PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares issued for new awards	(129,139)	0	0
2014 Three-year PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares issued for new awards	0	(636,723)	0
2013 Three-year PSU Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares issued for new awards	0	0	(1,074,017)
2002 Directors Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Director shares granted and issued	(10,560)	(15,491)	(18,022)
Director units granted and deferred (in shares)	(16,505)	(17,008)	(17,447)
2014 Omnibus Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
The maximum number of shares of Common Stock authorized				4,250,000
Restricted Stock \| Omnibus Incentive Plan and 2005 Contingent Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares forfeited (in shares)	(91,542)	(184,235)	(87,886)
Restricted Stock \| 2014 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares forfeited (in shares)	(5,024)
Restricted Stock Units (RSUs) \| Omnibus Incentive Plan and 2005 Contingent Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares issued for new awards	(219,923)	(351,946)	(428,595)
Restricted stock shares forfeited (in shares)	(64,122)	(288,801)	(29,774)
PSU And SLO Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Contingently issuable shares	1,000,000
Restricted Stock Units RSU SLO Awards \| Omnibus Incentive Plan and 2005 Contingent Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares issued for new awards	(23,478)	(44,254)	(81,614)
SLO Awards
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares issued for new awards	(109,841)	(136,783)	(20,587)
SLO Awards \| Omnibus Incentive Plan and 2005 Contingent Stock Plan
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]
Restricted stock shares forfeited (in shares)	(817)	(3,639)	0