This element represents the percentage of withholding tax payable by the entity.

No definition available.

Name:	nick_DividendDistributionWithholdingTaxPercentage
Namespace Prefix:	nick_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate dividends paid during the period for each share of common stock outstanding.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 505

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.3-04)

-URI http://asc.fasb.org/extlink&oid=6959260&loc=d3e187085-122770

+ Details

Name:	us-gaap_CommonStockDividendsPerShareCashPaid
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

+ Details

Name:	us-gaap_CommonStockDividendsPerShareDeclared
Namespace Prefix:	us-gaap_
Data Type:	num:perShareItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	us-gaap_SubsequentEventLineItems
Namespace Prefix:	us-gaap_
Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

Cash Dividend (Details) (USD $)	0 Months Ended							1 Months Ended	3 Months Ended		9 Months Ended
Cash Dividend (Details) (USD $)	Dec. 06, 2012	Dec. 11, 2012	Nov. 07, 2012	Sep. 06, 2012	Aug. 07, 2012	Jun. 06, 2012	May 02, 2012	Dec. 28, 2012	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2012	Dec. 31, 2011
Subsequent Event [Line Items]
Dividends declared per share (in dollars per share)		$ 2.00	$ 0.12		$ 0.12		$ 0.10		$ 2.12	$ 0.10	$ 2.34	$ 0.20
Dividend paid in cash (in dollars per share)	$ 0.12			$ 0.12		$ 0.10		$ 2.00			$ 2.34
Withholding tax payable percentage											5.00%