Variable Interest Entity (Detail Textuals)	12 Months Ended
Mar. 31, 2019 USD ($)
Variable Interest Entity [Abstract]
Monthly servicing fee percent of outstanding financed receivables	2.50%
Recourse to assets	$ 0

Variable interest entity monthly servicing fee percent of outstanding financed receivables.

No definition available.

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