Stockholders' Equity - Stock Option Grants, Activity And Expense (Details) $ / shares in Units, $ in Thousands		1 Months Ended			3 Months Ended
	Mar. 03, 2020 $ / shares shares	Dec. 31, 2020 USD ($) $ / shares shares	Mar. 31, 2020 $ / shares shares	Dec. 31, 2019 USD ($) $ / shares shares	Mar. 31, 2021 USD ($) individual $ / shares shares	Mar. 31, 2020 USD ($) $ / shares shares
2009 Stock Option Plan
Granted (in shares)						102,906,000
Other Disclosures
Number of option holders | individual					28
Compensation expense for stock options
Compensation expense (benefit) | $		$ 41		$ 19	$ 214	$ 122
Related tax benefit (expense) | $				$ 4		$ 28
Unrecognized compensation expense related to non-vested stock options that will be recognized during future periods
Balance of Fiscal 2021 | $					343
Fiscal 2022 | $					374
Fiscal 2023 | $					231
Fiscal 2024 | $					111
Fiscal 2025 | $					$ 15
INDUS stock option plan
Outstanding at beginning of period (in shares)					246,150,000	189,822,000
Adjustment for stock dividend (in shares)					5,413,000
Granted (in shares)						102,906,000
Exercised (in shares)					(233,000)
Outstanding at end of period (in shares)		246,150,000	292,728,000	189,822,000	251,330,000	292,728,000
Weighted Avg. Exercise Price
Outstanding at beginning of period (in dollars per share) | $ / shares					$ 36.06	$ 28.23
Adjustment for stock dividend (in dollars per share) | $ / shares					34.29
Granted (in dollars per share) | $ / shares						46.32
Exercised (in dollars per share) | $ / shares					26.31
Outstanding at end of period (in dollars per share) | $ / shares		$ 36.06	$ 34.59	$ 28.23	$ 35.28	$ 34.59
Employee
Compensation expense for stock options
Forfeiture rates (as a percent)					38.30%
Executives
Compensation expense for stock options
Forfeiture rates (as a percent)					17.90%
Minimum | Non-employee directors
Compensation expense for stock options
Forfeiture rates (as a percent)					0.00%
Maximum | Non-employee directors
Compensation expense for stock options
Forfeiture rates (as a percent)					2.00%
2009 Stock Option Plan
2009 Stock Option Plan
Expiration term	10 years
Number of options that may be exercised as stock appreciation rights					0
Granted (in shares)			49,061		0
Exercise price (in dollars per share) | $ / shares	$ 45.98		$ 44.99
INDUS stock option plan
Granted (in shares)			49,061		0
2020 Incentive Award Plan
2009 Stock Option Plan
Number of shares authorized	300,000
Granted (in shares)	52,000		53,149		0
Exercise price (in dollars per share) | $ / shares	$ 46.91		$ 45.90
INDUS stock option plan
Granted (in shares)	52,000		53,149		0
2020 Incentive Award Plan | Non-employee directors
2009 Stock Option Plan
Granted (in shares)						102,906
INDUS stock option plan
Granted (in shares)						102,906
2020 Incentive Award Plan | Minimum | Non-employee directors
2009 Stock Option Plan
Fair values of stock options granted (in dollars per share) | $ / shares						$ 12.29
2020 Incentive Award Plan | Maximum | Non-employee directors
2009 Stock Option Plan
Fair values of stock options granted (in dollars per share) | $ / shares						$ 14.17