CONSOLIDATED STATEMENT OF STOCKHOLDERS' EQUITY (DEFICIT) - USD ($) shares in Thousands, $ in Thousands	Total	Additional Paid-In Capital	Accumulated Deficit	Accumulated Other Comprehensive (Loss) Income	Noncontrolling Interests	Class A Common Stock Common Stock	Class B Common Stock Common Stock
Balance (in shares) at Apr. 30, 2013						38,662	988
Beginning balance at Apr. 30, 2013	$ 15,451	$ 335,857	$ (324,377)	$ (592)	$ 4,166	$ 387	$ 10
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(27,404)		(23,095)		(4,309)
Other comprehensive (loss) income	631			631
Issuances of Class A common stock	368	364				$ 4
Issuances of Class A common stock (in shares)						424
Stock-based compensation	2,404	2,404
Contributions from noncontrolling interest holders	13				13
Ending balance at Apr. 30, 2014	(8,537)	338,625	(347,472)	39	(130)	$ 391	$ 10
Balance (in shares) at Apr. 30, 2014						39,086	988
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(5,810)		(6,018)		208
Other comprehensive (loss) income	19			19
Issuances of Class A common stock	429	424				$ 5
Issuances of Class A common stock (in shares)						501
Stock-based compensation	1,639	1,639
Contributions from noncontrolling interest holders	155				155
Other	85	85			0
Ending balance at Dec. 31, 2014	(12,020)	340,773	(353,490)	58	233	$ 396	$ 10
Balance (in shares) at Dec. 31, 2014						39,587	988
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(11,781)		(12,969)		1,188
Other comprehensive (loss) income	(51)			(51)
Issuances of Class A common stock	486	481				$ 5
Issuances of Class A common stock (in shares)						477
Stock-based compensation	3,079	3,079
Distributions to noncontrolling interest holders	(1,495)				(1,495)
Other	185	185
Ending balance at Dec. 31, 2015	(21,597)	344,518	(366,459)	7	(74)	$ 401	$ 10
Balance (in shares) at Dec. 31, 2015						40,064	988
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(6,858)		(6,849)		(9)
Other comprehensive (loss) income	(75)			(75)
Issuances of Class A common stock	528	523				$ 5
Issuances of Class A common stock (in shares)						508
Stock-based compensation	3,393	3,393
Contributions from noncontrolling interest holders	59				59
Ending balance at Dec. 31, 2016	$ (24,550)	$ 348,434	$ (373,308)	$ (68)	$ (24)	$ 406	$ 10
Balance (in shares) at Dec. 31, 2016						40,572	988