Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5047-113901

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB Topic 14.F)
-URI http://asc.fasb.org/extlink&oid=115993241&loc=d3e301413-122809

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(1)(i)
-URI http://asc.fasb.org/extlink&oid=109197908&loc=d3e5070-113901

Stock-Based Compensation Plans (Details) - USD ($) $ / shares in Units, $ in Millions	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Apr. 30, 2014
Stock-Based Compensation Plans
Number of common shares reserved for issuance under the Equity Incentive Plan				2,850,000
Restricted stock awards
Stock-Based Compensation Plans
Unrecognized compensation cost	$ 2.8
Weighted average life over which unrecognized compensation is expected to be recognized	1 year 2 months 12 days
Number of Shares
Unvested at the beginning of the period (in shares)	918,344	1,114,625
Granted (in shares)	242,354	297,960
Vested (in shares)	(519,685)	(481,538)
Forfeited (in shares)		(12,703)
Unvested at the end of the period (in shares)	641,013	918,344	1,114,625
Weighted-Average Grant-Date Fair Value
Unvested at the beginning of the period (in dollars per share)	$ 15.67	$ 17.72
Granted (in dollars per share)	8.10	7.36
Vested (in dollars per share)	14.76	15.42
Forfeited (in dollars per share)		10.39
Unvested at the end of the period (in dollars per share)	$ 13.54	$ 15.67	$ 17.72
Restricted stock awards \| General and administrative expenses
Stock-Based Compensation Plans
Stock-based compensation expense	$ 5.5	$ 5.1	$ 4.4
Restricted stock awards \| Vest immediately
Stock-Based Compensation Plans
Vesting (as a percent)	25.00%	25.00%	25.00%
Restricted stock awards \| Vest one year after grant
Stock-Based Compensation Plans
Vesting (as a percent)	25.00%	25.00%	25.00%
Vesting period	1 year	1 year	1 year
Restricted stock awards \| Vest two years after grant
Stock-Based Compensation Plans
Vesting (as a percent)	25.00%	25.00%	25.00%
Vesting period	2 years	2 years	2 years
Restricted stock awards \| Vest three years after grant
Stock-Based Compensation Plans
Vesting (as a percent)	25.00%	25.00%	25.00%
Vesting period	3 years	3 years	3 years
Certain officers and employees \| Restricted stock awards
Stock-Based Compensation Plans
Number of common shares reserved for issuance under the Equity Incentive Plan	200,000	259,800	250,000
Non-executive director \| Restricted stock awards
Number of Shares
Granted (in shares)	35,295	31,800	31,770
Non-employee consultant \| Restricted stock awards
Number of Shares
Granted (in shares)	7,059	6,360	2,938