The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(iii)(1)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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- Definition

The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (c)(2)(i)-(ii)
-URI http://asc.fasb.org/extlink&oid=6415400&loc=d3e5070-113901

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Stockholders' Deficit - Summary of Grant Activity for Other Stock Awards (Detail) - $ / shares shares in Thousands	8 Months Ended	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2015	Apr. 30, 2014	Apr. 30, 2013
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Weighted Average Grant Date Fair Value		$ 4.40
2013 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted				735
2013 Grants [Member] \| Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted				340
Stock Awards, Weighted Average Grant Date Fair Value				$ 5.15
2013 Grants [Member] \| Performance Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted				316
Stock Awards, Weighted Average Grant Date Fair Value				$ 5.17
2013 Grants [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted				79
Stock Awards, Weighted Average Grant Date Fair Value				$ 4.45
2014 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted			542
Stock Awards, Unvested		149
2014 Grants [Member] \| Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted			482
Stock Awards, Weighted Average Grant Date Fair Value			$ 4.09
Stock Awards, Unvested		135
2014 Grants [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted			60
Stock Awards, Weighted Average Grant Date Fair Value			$ 5.81
Stock Awards, Unvested		14
Transition Period 2014 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted	370
Stock Awards, Unvested		215
Transition Period 2014 Grants [Member] \| Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted	277
Stock Awards, Weighted Average Grant Date Fair Value	$ 5.28
Stock Awards, Unvested		171
Transition Period 2014 Grants [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted	93
Stock Awards, Weighted Average Grant Date Fair Value	$ 3.78
Stock Awards, Unvested		44
2015 Grants [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted		624
Stock Awards, Unvested		598
2015 Grants [Member] \| Restricted Stock Units [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted		562
Stock Awards, Weighted Average Grant Date Fair Value		$ 4.20
Stock Awards, Unvested		541
2015 Grants [Member] \| Restricted Stock Awards [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock Awards, Granted		62
Stock Awards, Weighted Average Grant Date Fair Value		$ 6.25
Stock Awards, Unvested		57