Amount of expense for award under share-based payment arrangement. Excludes amount capitalized.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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Stock-Based Compensation Plans (Details) - USD ($) $ / shares in Units, $ in Millions	1 Months Ended		3 Months Ended		6 Months Ended
	Sep. 30, 2020	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Stock-Based Compensation Plans
Unrecognized compensation cost	$ 2.6		$ 2.6		$ 2.6
Weighted average life over which unrecognized compensation is expected to be recognized					2 years 2 months 19 days
General and administrative expenses
Stock-Based Compensation Plans
Stock-based compensation expense			$ 0.4	$ 0.9	$ 2.3	$ 2.2
Restricted stock awards
Stock-Based Compensation Plans
Granted (in shares)					415,679
Number of Shares
Unvested at the beginning of the period (in shares)					317,048
Granted (in shares)					415,679
Vested (in shares)					(374,406)
Forfeited (in shares)					(150)
Unvested at the end of the period (in shares)	358,171		358,171		358,171
Weighted-Average Grant-Date Fair Value
Unvested at the beginning of the period (in dollars per share)					$ 8.08
Granted (in dollars per share)					8.07
Vested (in dollars per share)					7.92
Forfeited (in dollars per share)					8.36
Unvested at the end of the period (in dollars per share)	$ 8.23		$ 8.23		$ 8.23
Certain officers and employees \| Restricted stock awards
Stock-Based Compensation Plans
Granted (in shares)		188,400
Number of Shares
Granted (in shares)		188,400
Certain officers and employees \| Restricted stock units
Stock-Based Compensation Plans
Granted (in shares)		56,450
Number of Shares
Granted (in shares)		56,450
Non-executive director \| Restricted stock awards
Stock-Based Compensation Plans
Granted (in shares)	7,600	7,575
Number of Shares
Granted (in shares)	7,600	7,575
President and Chief Executive Officer \| Restricted stock awards
Stock-Based Compensation Plans
Granted (in shares)		155,654
Number of Shares
Granted (in shares)		155,654