This element represents price at which option holders acquired shares when converting their stock options into shares.

No definition available.

Name:	nick_ShareBasedCompensationSharesExercisedUnderStockOptionPlansExercisePrice
Namespace Prefix:	nick_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

This element represents price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

+ References

No definition available.

+ Details

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Namespace Prefix:	nick_
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Balance Type:	na
Period Type:	duration

- 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.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 123R

-Paragraph A240

-Subparagraph i

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

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

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- 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.

+ References

+ Details

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Balance Type:	na
Period Type:	duration

- 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

+ Details

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Balance Type:	na
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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://www.xbrl.org/2003/role/presentationRef

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+ Details

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Balance Type:	na
Period Type:	duration

- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

+ References

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	na
Period Type:	duration

- Definition

Number of share options (or share units) exercised during the current period.

+ References

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-Name Accounting Standards Codification

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- Definition

Tax benefits realized from the exercise of stock options resulting in reductions in the entity's income taxes, which increases net cash provided by operating activities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 718

-SubTopic 20

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Share-Based Payments (Detail Textuals 1) (USD $)	12 Months Ended
Share-Based Payments (Detail Textuals 1) (USD $)	Mar. 31, 2013	Mar. 31, 2012	Mar. 31, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Cash received from exercise of option	$ 612,465	$ 830,277	$ 55,610
Stock options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of stock options exercised	97,594
Number of stock options forfeited	26,840
Cash received from exercise of option	612,000	830,000	56,000
Income tax benefits	262,000	511,000	64,000
Unrecognized compensation cost	477,000
Weighted-average period expected to be recognized	4 years
Stock options \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of stock options exercised	$ 0.77
Exercise price of stock options forfeited	$ 2.77
Stock options \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Exercise price of stock options exercised	$ 10.96
Exercise price of stock options forfeited	$ 12.96
Restricted stock
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unrecognized compensation cost	$ 776,000
Weighted-average period expected to be recognized	2 years
Number of shares awarded	85,000
Weighted average grant date fair value	$ 13.07
Performance Share Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares awarded	33,500
Weighted average grant date fair value	$ 13.11
Number of performance shares forfeited	23,000
Weighted average grant date fair value for forfeited shares	$ 13.04