SHARE-BASED COMPENSATION (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Additional Disclosures [Abstract]
Vested share-based awards withheld to satisfy income tax obligations (in shares)	37,086	54,546
Vested share-based awards withheld to satisfy income tax obligations	$ 3,600	$ 4,100
Compensation Expense [Abstract]
Share-based compensation expense	1,693	1,507
401(k) Profit Sharing Plan [Abstract]
Contribution to profit sharing plan	$ 500	$ 600
Restricted Stock [Member]
Number of Shares [Roll Forward]
Nonvested at beginning of period (in shares)	282,235
Granted (in shares)	70,688
Vested (in shares)	(118,492)
Forfeited (in shares)	(814)
Nonvested at end of period (in shares)	233,617
Weighted Average Grant-date Fair Value [Roll Forward]
Nonvested at beginning of period (in dollars per share)	$ 51.69
Granted (in dollars per share)	94.33
Vested (in dollars per share)	48.91
Forfeited (in dollars per share)	53.87
Nonvested at end of period (in dollars per share)	$ 66.00
Compensation Expense [Abstract]
Unrecognized compensation expense	$ 14,300
Unrecognized compensation expense, period for recognition	36 months
2017 Director LTIP [Member] \| Restricted Stock [Member]
Number of Shares [Roll Forward]
Granted (in shares)	841
2012 Employee LTIP [Member] \| Restricted Stock [Member]
Number of Shares [Roll Forward]
Granted (in shares)	69,847	66,530
Additional Disclosures [Abstract]
Vested share-based awards withheld to satisfy income tax obligations (in shares)	37,086
Vested share-based awards withheld to satisfy income tax obligations	$ 3,600
2008 Director LTIP [Member] \| Restricted Stock [Member]
Number of Shares [Roll Forward]
Granted (in shares)		282

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The amount of adjustment to stockholders' equity associated with an employee's income tax withholding obligation as part of a net-share settlement of a share-based award.

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No definition available.

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- Definition

Amount of cost for defined contribution plan.

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-Publisher FASB
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-SubTopic 70
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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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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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- Definition

The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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- Definition

Weighted average fair value as of the grant date of equity-based award plans other than stock (unit) option plans that were not exercised or put into effect as a result of the occurrence of a terminating event.

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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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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).

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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

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

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No definition available.

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

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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- Definition

For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

+ References

No definition available.

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