Consolidated Statements of Cash Flows (Unaudited) (USD $)	9 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Cash flows from operating activities
Net income	$ 13,008,445us-gaap_NetIncomeLoss	$ 13,843,813us-gaap_NetIncomeLoss
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	276,194us-gaap_DepreciationNonproduction	230,909us-gaap_DepreciationNonproduction
Loss (gain) on sale of property and equipment	6,691	(21,800)
Provision for credit losses	15,182,698	10,797,930
Amortization of dealer discounts	(10,204,562)us-gaap_AdjustmentForAmortization	(9,911,725)us-gaap_AdjustmentForAmortization
Deferred income taxes	270,675us-gaap_DeferredIncomeTaxExpenseBenefit	1,378,601us-gaap_DeferredIncomeTaxExpenseBenefit
Share-based compensation	382,883us-gaap_ShareBasedCompensation	405,264us-gaap_ShareBasedCompensation
Change in fair value of interest rate swap agreements	105,878	(681,989)
Changes in operating assets and liabilities:
Prepaid expenses and other assets	13,280	24,912
Accounts payable and accrued expenses	(2,572,286)	(728,528)
Income taxes receivable	447,340	(173,824)
Deferred revenues	574,862	654,952
Net cash provided by operating activities	17,492,098	15,818,515
Cash flows from investing activities
Purchase and origination of finance receivables	(119,758,892)	(111,941,584)
Principal payments received	101,279,098	99,626,856
Increase in assets held for resale	(345,644)nick_IncreaseInAssetsHeldForResale	(554,507)nick_IncreaseInAssetsHeldForResale
Purchase of property and equipment	(377,859)	(273,507)
Proceeds from sale of property and equipment	58,319	40,781
Net cash used in investing activities	(19,144,978)	(13,101,961)
Cash flows from financing activities
Net draws on line of credit	2,100,000	1,500,000
Change in drafts payable	(669,956)nick_IncreaseDecreaseInDraftsPayable	(525,556)nick_IncreaseDecreaseInDraftsPayable
Payment of cash dividends		(2,851,126)us-gaap_PaymentsOfDividends
Proceeds from exercise of stock options	154,575	275,772
Excess tax benefits from share-based compensation	69,016	176,106
Net cash provided (used) by financing activities	1,653,635	(1,424,804)
Net increase in cash	755us-gaap_CashPeriodIncreaseDecrease	1,291,750us-gaap_CashPeriodIncreaseDecrease
Cash, beginning of period	2,635,036us-gaap_Cash	2,797,716us-gaap_Cash
Cash, end of period	$ 2,635,791us-gaap_Cash	$ 4,089,466us-gaap_Cash

The increase (decrease) during the reporting in the amount of Draft payable.

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Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Excludes cash and cash equivalents within disposal group and discontinued operation.

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