Summary of Significant Accounting Policies, Net Income Per Share (Details) - USD ($)	3 Months Ended								12 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2020	Mar. 31, 2019	Mar. 31, 2018
Reconciliation of basic and diluted net income (loss) per share [Abstract]
Net (loss) income	$ (8,193,000)	$ 865,000	$ 6,189,000	$ (6,151,000)	$ (2,765,000)	$ (3,102,000)	$ 3,513,000	$ (5,495,000)	$ (7,290,000)	$ (7,849,000)	$ 19,264,000
Basic shares (in shares)									18,913,788	18,849,909	18,854,993
Effect of dilutive stock options and warrants (in shares)									0	0	659,782
Diluted shares (in shares)									18,913,788	18,849,909	19,514,775
Net (loss) income per share [Abstract]
Basic net (loss) income per share (in dollars per share)	$ (0.43)	$ 0.05	$ 0.33	$ (0.33)	$ (0.15)	$ (0.16)	$ 0.19	$ (0.29)	$ (0.39)	$ (0.42)	$ 1.02
Diluted net (loss) income per share (in dollars per share)	$ (0.43)	$ 0.04	$ 0.32	$ (0.33)	$ (0.15)	$ (0.16)	$ 0.18	$ (0.29)	$ (0.39)	$ (0.42)	$ 0.99
Options [Member]
Antidilutive Securities [Abstract]
Antidilutive securities excluded from effect of dilutive options and warrants (in shares)									1,738,106	1,580,299	448,039