Fair Value Measurements - Financial Assets and Liabilities (Details) - USD ($) $ in Thousands	1 Months Ended	6 Months Ended		12 Months Ended
	Apr. 30, 2019	Mar. 31, 2021	Mar. 31, 2020	Sep. 30, 2020	Apr. 01, 2019
Financial liabilities:
Interest on note receivable	2.89%
Notes receivable from Grupo Finmart, net | Carrying Value
Financial assets:
Notes receivable, fair value			$ 3,728
Notes receivable from Grupo Finmart, net | Estimated Fair Value
Financial assets:
Notes receivable, fair value			3,853
Notes receivable from Grupo Finmart, net | Estimated Fair Value | Level 1
Financial assets:
Notes receivable, fair value			0
Notes receivable from Grupo Finmart, net | Estimated Fair Value | Level 2
Financial assets:
Notes receivable, fair value			0
Notes receivable from Grupo Finmart, net | Estimated Fair Value | Level 3
Financial assets:
Notes receivable, fair value			$ 3,853
2.89% promissory note receivable due April 2024
Financial assets:
Notes receivable, fair value					$ 1,100
Financial liabilities:
Interest on note receivable	2.89%	2.89%	2.89%	2.89%
2.89% promissory note receivable due April 2024 | Carrying Value
Financial assets:
Notes receivable, fair value		$ 1,164	$ 1,132	$ 1,148
2.89% promissory note receivable due April 2024 | Estimated Fair Value
Financial assets:
Notes receivable, fair value		1,164	1,132	1,148
2.89% promissory note receivable due April 2024 | Estimated Fair Value | Level 1
Financial assets:
Notes receivable, fair value		0	0	0
2.89% promissory note receivable due April 2024 | Estimated Fair Value | Level 2
Financial assets:
Notes receivable, fair value		0	0	0
2.89% promissory note receivable due April 2024 | Estimated Fair Value | Level 3
Financial assets:
Notes receivable, fair value		1,164	1,132	1,148
Investments in unconsolidated affiliates | Carrying Value
Financial assets:
Investments in unconsolidated affiliates, fair value		34,961	27,993	32,458
Investments in unconsolidated affiliates | Estimated Fair Value
Financial assets:
Investments in unconsolidated affiliates, fair value		45,491	27,513	32,597
Investments in unconsolidated affiliates | Estimated Fair Value | Level 1
Financial assets:
Investments in unconsolidated affiliates, fair value		37,894	19,734	24,833
Investments in unconsolidated affiliates | Estimated Fair Value | Level 2
Financial assets:
Investments in unconsolidated affiliates, fair value		0	0	0
Investments in unconsolidated affiliates | Estimated Fair Value | Level 3
Financial assets:
Investments in unconsolidated affiliates, fair value		7,597	7,779	7,764
2024 Convertible Notes | Carrying Value
Financial liabilities:
Debt instruments, fair value		120,307	114,196	117,193
2024 Convertible Notes | Estimated Fair Value
Financial liabilities:
Debt instruments, fair value		132,609	106,203	129,979
2024 Convertible Notes | Estimated Fair Value | Level 1
Financial liabilities:
Debt instruments, fair value		0	0	0
2024 Convertible Notes | Estimated Fair Value | Level 2
Financial liabilities:
Debt instruments, fair value		132,609	106,203	129,979
2024 Convertible Notes | Estimated Fair Value | Level 3
Financial liabilities:
Debt instruments, fair value		0	0	0
2025 Convertible Notes | Carrying Value
Financial liabilities:
Debt instruments, fair value		136,836	129,624	133,164
2025 Convertible Notes | Estimated Fair Value
Financial liabilities:
Debt instruments, fair value		143,175	128,081	137,569
2025 Convertible Notes | Estimated Fair Value | Level 1
Financial liabilities:
Debt instruments, fair value		0	0	0
2025 Convertible Notes | Estimated Fair Value | Level 2
Financial liabilities:
Debt instruments, fair value		143,175	128,081	137,569
2025 Convertible Notes | Estimated Fair Value | Level 3
Financial liabilities:
Debt instruments, fair value		$ 0	$ 0	$ 0
8.5% unsecured debt due 2024
Financial liabilities:
Stated interest rate			8.50%	8.50%
8.5% unsecured debt due 2024 | Carrying Value
Financial liabilities:
Debt instruments, fair value			$ 983	$ 872
8.5% unsecured debt due 2024 | Estimated Fair Value
Financial liabilities:
Debt instruments, fair value			983	872
8.5% unsecured debt due 2024 | Estimated Fair Value | Level 1
Financial liabilities:
Debt instruments, fair value			0	0
8.5% unsecured debt due 2024 | Estimated Fair Value | Level 2
Financial liabilities:
Debt instruments, fair value			0	0
8.5% unsecured debt due 2024 | Estimated Fair Value | Level 3
Financial liabilities:
Debt instruments, fair value			983	$ 872
CASHMAX secured borrowing facility | Carrying Value
Financial liabilities:
Debt instruments, fair value			(248)
CASHMAX secured borrowing facility | Estimated Fair Value
Financial liabilities:
Debt instruments, fair value			281
CASHMAX secured borrowing facility | Estimated Fair Value | Level 1
Financial liabilities:
Debt instruments, fair value			0
CASHMAX secured borrowing facility | Estimated Fair Value | Level 2
Financial liabilities:
Debt instruments, fair value			0
CASHMAX secured borrowing facility | Estimated Fair Value | Level 3
Financial liabilities:
Debt instruments, fair value			$ 281