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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No definition available.

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- Definition

Distribution payment period.

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- Definition

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

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- Definition

Optional Payment Installments Annual

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No definition available.

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- Definition

Postretirement Benefits Plan Vesting Period

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No definition available.

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- Definition

Share Based Compensation Agreement Cash Settlement Price Per Share

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No definition available.

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- Definition

Time based stock vesting period.

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No definition available.

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- Definition

Amount of commitment made to pay deferred cash remuneration.

+ References

No definition available.

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- Definition

The total fair value of shares issued during the period under a deferred compensation arrangement.

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- Definition

Unrecognized cost of unvested share-based compensation awards.

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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 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

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

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

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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

+ References

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- Definition

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

+ 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

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

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- Definition

Amount by which the current fair value of the underlying stock exceeds the exercise price of fully vested and expected to vest options outstanding.

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- Definition

Maximum number of shares that may be issued in accordance with the plan as a proportion of outstanding capital stock.

+ References

No definition available.

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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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Stock-Based Compensation and Incentive Plans - Additional Information (Detail)	12 Months Ended
	Mar. 31, 2017 USD ($) Installment $ / shares shares	Mar. 31, 2015 $ / shares shares	Mar. 31, 2014 USD ($) Installment / yr $ / shares shares	Mar. 31, 2013 USD ($)	Mar. 31, 2016 $ / shares shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Options outstanding \| shares	1,395,548	1,709,206	1,370,056		1,777,124
Intrinsic value of options outstanding	$ 0
Intrinsic value of options exercisable	$ 0
Fair value of non-vested shares \| $ / shares	$ 24.19	$ 39.53	$ 48.68		$ 23.58
Director stock payment period			15 days	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%
Distribution payment period	15 days
Director
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Value of stock units granted			$ 115,000	$ 100,000
Director \| Deferred Cash Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Value of cash awards granted	$ 97,750
Minimum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period	3 months
Optional payment installments, annual \| Installment / yr			2
Minimum \| Deferred Cash Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Optional payment installments, annual \| Installment	2
Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Option expiration period	10 years
Optional payment installments, annual \| Installment / yr			10
Maximum \| Deferred Cash Award
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Optional payment installments, annual \| Installment	10
Stock Options
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
General vesting period, years	3 years
Post retirement period to exercise vested options	2 years
Total unrecognized stock compensation costs	$ 1,500,000
Total unrecognized stock compensation costs, net of tax	$ 1,100,000
Restricted Stock
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Time-based stock vesting period, years	4 years
Fair value of non-vested shares \| $ / shares		56.94	$ 54.75
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 \| shares	183
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	$ 1,100,000
Total unrecognized stock compensation costs, net of tax	$ 800,000
Fair value of non-vested shares \| $ / shares	$ 9.74	24.07	$ 50.94		10.83
Phantom Stock Plan \| Time Based Restricted Stock Awards
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Share based compensation outstanding number \| shares	566,638
Phantom Stock Plan \| Non-Vested Shares
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Fair value of non-vested shares \| $ / shares	$ 1.15
Cash-based Performance Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Total unrecognized stock compensation costs	$ 2,100,000
Total unrecognized stock compensation costs, net of tax	$ 1,400,000
Share based compensation outstanding number \| shares	4,296,392
Fair value of non-vested shares \| $ / shares	$ 1.16	1.10			$ 1.16
Cash-based Performance Plan \| Maximum
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Units awarded, vesting rights amount \| $ / shares		$ 2
2017 Stock Incentive Plan
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of common equity available for grant	8.00%
2017 Stock Incentive Plan \| Time-based Restricted Stock Units
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of common equity available for grant	3.00%
Option expiration period	30 days
2017 Stock Incentive Plan \| Available for Future Grants
Share Based Compensation Arrangement By Share Based Payment Award [Line Items]
Percentage of common equity available for grant	5.00%