CONDENSED CONSOLIDATED STATEMENTS OF STOCKHOLDERS' AND MEMBERS' EQUITY (Unaudited) - USD ($) $ in Thousands	Members Equity [Member]	Common Stock [Member] Class A Common Stock [Member]	Common Stock [Member] Class B Common Stock [Member]	Additional Paid-in Capital [Member]	Retained Earnings [Member]	Noncontrolling Interest [Member]	Total
Beginning balance at Sep. 30, 2018							$ 79,965
Increase (Decrease) in Temporary Equity [Roll Forward]
Distributions to members							(823)
Accumulated unpaid preferred returns							2,057
Accretion of redeemable preferred and issuance costs							157
Beginning balance at Dec. 31, 2018							81,536
Beginning balance at Sep. 30, 2018	$ 15,963	$ 0	$ 0	$ 0	$ 0	$ 5,093	21,056
Beginning balance (in shares) at Sep. 30, 2018		0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	2,234	$ 0	$ 0	0	0	276	2,510
Distributions to members	(126)	0	0	0	0	(500)	(626)
Accumulated unpaid preferred returns	(2,057)	0	0	0	0	0	(2,057)
Accretion of redeemable preferred and issuance costs	(157)	0	0	0	0	0	(157)
Equity-based compensation	39	0	0	0	0	0	39
Ending balance at Dec. 31, 2018	15,896	$ 0	$ 0	0	0	4,869	20,765
Ending balance (in shares) at Dec. 31, 2018		0	0
Beginning balance at Sep. 30, 2018							79,965
Beginning balance at Mar. 31, 2019							83,620
Beginning balance at Sep. 30, 2018	15,963	$ 0	$ 0	0	0	5,093	21,056
Beginning balance (in shares) at Sep. 30, 2018		0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income							(441)
Ending balance at Mar. 31, 2019	9,350	$ 0	$ 0	0	0	5,139	14,489
Ending balance (in shares) at Mar. 31, 2019		0	0
Beginning balance at Dec. 31, 2018							81,536
Increase (Decrease) in Temporary Equity [Roll Forward]
Accumulated unpaid preferred returns							2,108
Accretion of redeemable preferred and issuance costs							156
Beginning balance at Mar. 31, 2019							83,620
Beginning balance at Dec. 31, 2018	15,896	$ 0	$ 0	0	0	4,869	20,765
Beginning balance (in shares) at Dec. 31, 2018		0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(3,221)	$ 0	$ 0	0	0	270	(2,951)
Distributions to members	(1,099)	0	0	0	0	0	(1,099)
Accumulated unpaid preferred returns	(2,108)	0	0	0	0	0	(2,108)
Accretion of redeemable preferred and issuance costs	(156)	0	0	0	0	0	(156)
Equity-based compensation	38	0	0	0	0	0	38
Ending balance at Mar. 31, 2019	9,350	$ 0	$ 0	0	0	5,139	14,489
Ending balance (in shares) at Mar. 31, 2019		0	0
Beginning balance at Sep. 30, 2019							86,018
Increase (Decrease) in Temporary Equity [Roll Forward]
Distributions to members							(1,310)
Accumulated unpaid preferred returns							2,183
Accretion of redeemable preferred and issuance costs							162
Beginning balance at Dec. 31, 2019							87,053
Beginning balance at Sep. 30, 2019	31,770	$ 0	$ 0	0	0	6,199	37,969
Beginning balance (in shares) at Sep. 30, 2019		0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income	(1,314)	$ 0	$ 0	0	0	247	(1,067)
Distributions to members	(189)	0	0	0	0	(732)	(921)
Accumulated unpaid preferred returns	(2,183)	0	0	0	0	0	(2,183)
Accretion of redeemable preferred and issuance costs	(162)	0	0	0	0	0	(162)
Equity-based compensation	39	0	0	0	0	0	39
Ending balance at Dec. 31, 2019	27,961	$ 0	$ 0	0	0	5,714	33,675
Ending balance (in shares) at Dec. 31, 2019		0	0
Beginning balance at Sep. 30, 2019							86,018
Beginning balance at Mar. 31, 2020							0
Beginning balance at Sep. 30, 2019	31,770	$ 0	$ 0	0	0	6,199	37,969
Beginning balance (in shares) at Sep. 30, 2019		0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income							1,912
Ending balance at Mar. 31, 2020	0	$ 61	$ 85	56,730	1,085	80,706	138,667
Ending balance (in shares) at Mar. 31, 2020		6,087,906	8,462,392
Beginning balance at Dec. 31, 2019							87,053
Beginning balance at Mar. 31, 2020							0
Beginning balance at Dec. 31, 2019	27,961	$ 0	$ 0	0	0	5,714	33,675
Beginning balance (in shares) at Dec. 31, 2019		0	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net (loss) income							2,979
Ending balance at Mar. 31, 2020	$ 0	$ 61	$ 85	$ 56,730	$ 1,085	$ 80,706	$ 138,667
Ending balance (in shares) at Mar. 31, 2020		6,087,906	8,462,392