Deferred compensation arrangement with individual cash awards interest rate applicable margin.

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- Definition

Director Stock Payment Period in Days

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- Definition

Employee service sharebased compensation nonvested awards compensation cost not yet recognized net of tax.

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- Definition

Postretirement Benefits Plan Vesting Period

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- Definition

Share based compensation expense (benefit).

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- Definition

Represents the expense 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.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
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- Definition

Amount of commitment made to pay deferred cash remuneration.

+ References

No definition available.

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- Definition

The compensation expense recognized during the period pertaining to the deferred compensation arrangement.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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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- 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.

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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).

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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- Definition

The weighted average fair value of nonvested awards on equity-based plans excluding option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, revenue or profit achievement stock award plan) for which the employer is contingently obligated to issue equity instruments or transfer assets to an employee who has not yet satisfied service or performance criteria necessary to gain title to proceeds from the sale of the award or underlying shares or units.

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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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- Definition

Net number of non-option equity instruments granted to participants.

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- Definition

Number of equity instruments other than options outstanding, including both vested and non-vested instruments.

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- Definition

The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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- Definition

The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

Gross number of share options (or share units) granted during the period.

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No definition available.

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Number of options outstanding, including both vested and non-vested options.

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- Definition

Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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Number of fully vested and expected to vest options outstanding that can be converted into shares under option plan. Includes, but is not limited to, unvested options for which requisite service period has not been rendered but that are expected to vest based on achievement of performance condition, if forfeitures are recognized when they occur.

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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.

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Fair value of options vested. Excludes equity instruments other than options, for example, but not limited to, share units, stock appreciation rights, restricted stock.

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Stock-Based Compensation and Incentive Plans - Additional Information (Detail) - USD ($)			1 Months Ended	4 Months Ended	5 Months Ended	9 Months Ended	12 Months Ended
	Mar. 31, 2017	Mar. 31, 2016	Mar. 31, 2018	Jul. 31, 2017	Dec. 31, 2017	Dec. 31, 2017	Dec. 31, 2018	Dec. 31, 2017	Mar. 31, 2017
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option awards outstanding					0	0	0	0
Number of stock options vested	266,000								266,000
Fair value of stock options vested									$ 1,200,000
Number of options exercisable	1,000,000								1,000,000
Weighted average exercise price of options exercisable	$ 34.36								$ 34.36
Director stock payment period							15 days
Deferred Cash Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Interest rate, applicable margin to 10 year Treasury note									1.50%
Deferred cash award expense				$ 10,000					$ 1,000,000
Deferred Stock Unit
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Compensation expense (benefit)				$ 100,000					2,000,000
Director \| Deferred Cash Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Value of cash awards granted	$ 97,750								$ 97,750
2017 Stock Incentive Plan \| Plan of Reorganization
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
General vesting period, years								3 years
Deferred Stock Unit Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
New awards have been issued	0	0
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period							3 months
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period							10 years
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option awards outstanding							1,395,548
General vesting period, years							3 years
Post retirement period to exercise vested options							2 years
Stock options granted						0	0		0
Weighted average exercise price							$ 28.14
Restricted Stock Units (RSUs)
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized stock compensation costs					$ 24,500,000	$ 24,500,000	$ 22,600,000	$ 24,500,000
Unrecognized compensation costs, weighted-average recognition period							2 years
Total unrecognized stock compensation costs, net of tax					18,200,000	$ 18,200,000	$ 17,100,000	$ 18,200,000
Compensation expense					3,731,000		$ 13,504,000
Restricted Stock Units (RSUs) \| Time Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation outstanding number							559,608
Restricted Stock Units (RSUs) \| 2017 Stock Incentive Plan \| Plan of Reorganization \| Director
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
General vesting period, years								1 year
Restricted Stock Units (RSUs) \| 2017 Stock Incentive Plan \| Plan of Reorganization \| CEO
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
General vesting period, years			3 years
Phantom Stock Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
General vesting period, years							3 years
Total unrecognized stock compensation costs							$ 30,000
Total unrecognized stock compensation costs, net of tax							$ 10,000
New awards issued							0
Compensation expense					$ 94,000		$ 214,000
Phantom Stock Plan \| Series A Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of non-vested shares					$ 1.00	$ 1.00	$ 1.00	$ 1.00
Number of units outstanding					21,934	21,934	7,650	21,934
Phantom Stock Plan \| Series B Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of non-vested shares					$ 0.98	$ 0.98	$ 2.94	$ 0.98
Number of units outstanding					23,712	23,712	8,269	23,712
Phantom Stock Plan \| Time Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation outstanding number							4,517
Fair value of non-vested shares					$ 308.24	$ 308.24	$ 226.50	$ 308.24
Number of units outstanding					13,526	13,526	4,517	13,526
Phantom Stock Plan \| Non-Vested Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of non-vested shares							$ 19.13
Phantom Stock Plan \| Non-Vested Shares \| Series A Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of non-vested shares							1.67
Phantom Stock Plan \| Non-Vested Shares \| Series B Warrants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of non-vested shares							$ 1.40
Cash-based Performance Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of non-vested shares	$ 1.16								$ 1.16
Number of units outstanding	0.2			7.7	0	0	0	0	0.2
Compensation expense				$ 2,000,000					$ 800,000