Segments Long-Lived Assets (Details) - USD ($)	3 Months Ended		9 Months Ended		12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2017
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	$ 136,933,767	$ 130,814,842	$ 396,848,721	$ 387,163,914
Disclosure on Geographic Areas, Long-Lived Assets			24972580		24184207
Provision for Loan and Lease Losses	43,754,905	39,984,838	$ 113,570,935	107,869,859
General and Administrative Expense	72,886,385	71,236,778	216,712,225	197,641,071
Interest Expense	5,000,504	5,274,436	14,037,950	16,379,633
Income Tax Expense (Benefit)	13,611,756	4,678,757	27,980,363	23,523,899
Net Income (Loss) Attributable to Parent	1,680,217	9,640,033	24,547,248	41,749,452	$ 73,600,294
UNITED STATES
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	125,702,639	120,510,039	$ 361,270,056	356,187,410
Disclosure on Geographic Areas, Long-Lived Assets			22174609		20724777
Provision for Loan and Lease Losses	40,455,513	37,563,370	$ 100,989,538	100,911,353
General and Administrative Expense	68,680,112	65,216,354	193,825,300	180,147,990
Interest Expense	5,000,504	5,274,436	14,037,950	16,379,633
Income Tax Expense (Benefit)	13,729,880	4,405,439	28,979,799	21,677,028
Net Income (Loss) Attributable to Parent	(2,163,370)	8,050,440	23,437,469	37,071,406
MEXICO
Revenues from External Customers and Long-Lived Assets [Line Items]
Revenues	11,231,128	10,304,803	$ 35,578,665	30,976,504
Disclosure on Geographic Areas, Long-Lived Assets			2797971		3459430
Provision for Loan and Lease Losses	3,299,392	2,421,468	$ 12,581,397	6,958,506
General and Administrative Expense	4,206,273	6,020,424	22,886,925	17,493,081
Interest Expense	0	0	0	0
Income Tax Expense (Benefit)	(118,124)	273,318	(999,436)	1,846,871
Net Income (Loss) Attributable to Parent	$ 3,843,587	$ 1,589,593	$ 1,109,779	$ 4,678,046