Quarterly report pursuant to Section 13 or 15(d)

Commitments and Contingencies (Detail)

Commitments and Contingencies (Detail) $ in Thousands		1 Months Ended			2 Months Ended	3 Months Ended		5 Months Ended	9 Months Ended	12 Months Ended	24 Months Ended
Commitments and Contingencies (Detail) $ in Thousands	Feb. 01, 2016 USD ($)	Oct. 31, 2016 plaintiff	Nov. 30, 2015 claim	Sep. 30, 2015 USD ($)	Jan. 31, 2015 USD ($) note_offering plaintiff claim	Sep. 30, 2016 USD ($)	Jul. 31, 2016 USD ($) claim	Jun. 30, 2016 plaintiff claim	Sep. 30, 2016 USD ($)	Feb. 29, 2016 plaintiff claim	Dec. 31, 2014 USD ($) security_offering firm underwriter
Loss Contingencies [Line Items]
Number of prior note offerings \| note_offering					3
Number of firms that underwrote security offerings \| firm											9
Number of security offerings \| security_offering											6
Loss contingency accrual, product liability						$ 3,224			$ 3,224
Charges to operations						3,584			5,384
Term of contract	14 years
2016	$ 1,791
2017						1,791			1,791
2018	$ 1,954
Increase per year thereafter, percent	2.00%
Aggregate commitment						$ 49,821			$ 49,821
Ladenburg
Loss Contingencies [Line Items]
New claims filed, number \| claim							4
Number of security offerings \| security_offering											2
Damages sought by plaintiff							$ 4,300
Number of underwriters \| underwriter											1
Subsidiaries
Loss Contingencies [Line Items]
Term of contract	12 years
Annual rental payments	$ 1,811
Compensatory damages
Loss Contingencies [Line Items]
New claims filed, number \| claim			2		2
Number of plaintiffs \| plaintiff					17
Damages sought by plaintiff											$ 151,000
Compensatory damages \| Ladenburg
Loss Contingencies [Line Items]
Damages sought by plaintiff											$ 2,900,000
Compensatory damages \| Triad
Loss Contingencies [Line Items]
New claims filed, number \| claim										8
Number of plaintiffs \| plaintiff								2		45
New lawsuits filed, number \| claim										1
Number of claims settled \| claim								8
Number of claims pending decision \| claim
Convertible Notes Payable
Loss Contingencies [Line Items]
Proceeds from issuance Public Offering					$ 300,000
Common Stock
Loss Contingencies [Line Items]
Proceeds from issuance Public Offering					$ 1,656,000
Pending Litigation \| Compensatory damages \| Triad
Loss Contingencies [Line Items]
Damages sought by plaintiff				$ 3,714
ARCP July 2013 Offering \| Compensatory damages
Loss Contingencies [Line Items]
Number of plaintiffs \| plaintiff					8
Subsequent Event \| Securities America
Loss Contingencies [Line Items]
Number of plaintiffs \| plaintiff		2