Income Taxes (Details 1) - USD ($)	3 Months Ended								12 Months Ended
	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Investments, Owned, Federal Income Tax Note [Line Items]
Deferred Tax Assets, Valuation Allowance, Current	$ 1,274				$ 3,256,200				$ 1,274	$ 3,256,200
TaxCutsAndJobsActOf2017IncomeTaxExpenseBenefit									(852,523)	10,516,827
Significant Change in Unrecognized Tax Benefits is Reasonably Possible, Amount of Unrecorded Benefit	1,809,244								1,809,244
Operating Loss Carryforwards	54,318								54,318
Deferred Income Tax Expense (Benefit) [Abstract]
Deferred income tax benefit									(3,655,751)	8,785,432	$ (894,086)
Income tax expense reconciliation to U.S. federal tax rate [Abstract]
Expected income tax									18,874,500	30,556,455	37,081,756
Discontinued Operation, Tax Effect of Discontinued Operation									626,583	(243,321)	2,239,345
Increase (reduction) in income taxes resulting from:
State tax, net of federal benefit									1,576,915	2,249,055	2,106,957
Insurance income exclusion											0
Uncertain tax positions									(183,929)	(340,993)	(1,015,222)
Tax Adjustments, Settlements, and Unusual Provisions									0	0	238,301
Other, net									270,674	(78,176)	(254,300)
Income taxes	6,984,000	$ 834,000	$ 3,604,000	$ 4,559,000	18,778,000	$ 15,204,000	$ 6,511,000	$ 7,265,000	15,981,057	47,757,808	38,157,492
Effective Income Tax Rate Reconciliation, Tax Credit, Amount									(3,704,580)	0	0
Deferred tax assets:
Allowance for doubtful accounts	20,162,369				16,263,086				20,162,369	16,263,086
Unearned insurance commissions	9,308,138				8,711,298				9,308,138	8,711,298
Deferred Tax Assets, Tax Deferred Expense, Compensation and Benefits, Employee Benefits	9,271,182				8,470,247				9,271,182	8,470,247
Deferred Tax Assets, Tax Deferred Expense, Reserves and Accruals	1,011,584				795,259				1,011,584	795,259
Deferred Tax Assets, Tax Credit Carryforwards, Foreign	3,254,926								3,254,926
Convertible notes					3,254,926					3,254,926
Gross deferred tax assets	51,885,650				37,494,816				51,885,650	37,494,816
Less valuation allowance	(11,112,376)				(3,256,200)				(11,112,376)	(3,256,200)
Net deferred tax assets	40,773,274				34,238,616				40,773,274	34,238,616
Deferred tax liabilities:
Fair value adjustment for loans	(9,589,188)				(6,556,078)				(9,589,188)	(6,556,078)
Property and equipment	(2,426,786)				(2,957,534)				(2,426,786)	(2,957,534)
Intangible assets	(1,610,258)				(1,592,173)				(1,610,258)	(1,592,173)
Deferred net loan origination fees	(1,593,385)				(1,402,733)				(1,593,385)	(1,402,733)
Prepaid expenses	(1,054,110)				(1,554,950)				(1,054,110)	(1,554,950)
Gross deferred tax liabilities	(16,942,375)				(14,063,468)				(16,942,375)	(14,063,468)
Deferred Tax Liabilities, Other	(668,648)				0				(668,648)	0
Net deferred tax assets	23,830,899				20,175,148				23,830,899	20,175,148
Reconciliation of the beginning and ending amount of unrecognized tax benefits [Roll Forward]
Unrecognized tax benefits balance at beginning of period				$ 6,946,229				$ 7,264,966	6,946,229	7,264,966	9,395,413
Gross increases for tax positions of current year									54,025		(237,746)
Gross increases for tax positions of prior years									(138,405)	8,228	637,166
Federal and state tax settlements									1,356,714	0	2,403,982
Lapse of statute of limitations									(1,461,512)	(493,340)	(125,885)
Unrecognized tax benefits balance at end of period	4,043,623				6,946,229				4,043,623	6,946,229	7,264,966
Unrecognized Tax Benefits, Interest on Income Taxes Accrued	1,766,989				$ 1,863,400				$ 1,766,989	1,863,400	1,641,916
Current Fiscal Year End Date									--03-31
Discontinued Operations, Disposed of by Sale [Member]
Income tax expense reconciliation to U.S. federal tax rate [Abstract]
Expected income tax									$ 491,783	1,373,566	2,817,240
Discontinued Operation, Tax Effect of Discontinued Operation									187,974	5,483	(332,023)
Increase (reduction) in income taxes resulting from:
Other, net									(53,174)	(1,622,370)	(245,872)
Income taxes									626,583	(243,321)	2,239,345
Continuing Operations [Member]
Current Income Tax Expense (Benefit) [Abstract]
U.S. Federal									20,508,247	32,398,898	34,930,677
State and local									(871,439)	3,191,525	3,215,621
Current income tax expense									19,636,808	35,590,423	38,146,298
Deferred Income Tax Expense (Benefit) [Abstract]
U.S. Federal									(1,833,943)	12,073,220	(14,658)
State and local									(1,821,808)	94,165	25,852
Deferred income tax benefit									(3,655,751)	12,167,385	11,194
Income Tax Expense (Benefit) [Abstract]
U.S. Federal									18,674,304	44,472,118	34,916,019
State and local									(2,693,247)	3,285,690	3,241,473
Increase (reduction) in income taxes resulting from:
Income taxes									15,981,057	47,757,808	38,157,492
MEXICO
Investments, Owned, Federal Income Tax Note [Line Items]
TaxCutsAndJobsActOf2017IncomeTaxExpenseBenefit									0	$ 4,854,640	0
Increase (reduction) in income taxes resulting from:
Income taxes											$ 2,239,345
Domestic Tax Authority [Member]
Investments, Owned, Federal Income Tax Note [Line Items]
Operating Loss Carryforwards	25,900,000								25,900,000
Discontinued Operations, Disposed of by Sale [Member]
Investments, Owned, Federal Income Tax Note [Line Items]
Operating Loss Carryforwards	$ 37,400,000								$ 37,400,000