Quarterly report pursuant to Section 13 or 15(d)

Fair Value Measurements - National Financial Instruments Measured at Fair Value on Recurring Basis (Detail)

v3.7.0.1
Fair Value Measurements - National Financial Instruments Measured at Fair Value on Recurring Basis (Detail) - USD ($)
$ in Thousands
Mar. 31, 2017
Dec. 31, 2016
Assets    
Long-term investments, at fair value $ 746  
Total 746  
Liabilities    
Liabilities 5,186  
National Holdings Corporation [Member]    
Assets    
Total   $ 1,206
Liabilities    
Liabilities   10,097
Contingently Issuable Warrant [Member]    
Liabilities    
Liabilities 298  
Warrant [Member]    
Liabilities    
Liabilities 104  
Helocyte Convertible Note One [Member]    
Liabilities    
Liabilities 4,580  
Avenue Convertible Note [Member]    
Liabilities    
Liabilities 204  
Corporate stock Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   172
Municipal bonds Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   930
Restricted stock Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   104
Corporate stock Liabilities [Member] | National Holdings Corporation [Member]    
Liabilities    
Liabilities   1
Warrants Issuable [Member] | National Holdings Corporation [Member]    
Liabilities    
Liabilities   10,096
Fair Value, Inputs, Level 1 [Member]    
Assets    
Long-term investments, at fair value 0  
Total 0  
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 1 [Member] | National Holdings Corporation [Member]    
Assets    
Total   1,102
Liabilities    
Liabilities   1
Fair Value, Inputs, Level 1 [Member] | Contingently Issuable Warrant [Member]    
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 1 [Member] | Warrant [Member]    
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 1 [Member] | Helocyte Convertible Note One [Member]    
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 1 [Member] | Avenue Convertible Note [Member]    
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 1 [Member] | Corporate stock Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   172
Fair Value, Inputs, Level 1 [Member] | Municipal bonds Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   930
Fair Value, Inputs, Level 1 [Member] | Restricted stock Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   0
Fair Value, Inputs, Level 1 [Member] | Corporate stock Liabilities [Member] | National Holdings Corporation [Member]    
Liabilities    
Liabilities   1
Fair Value, Inputs, Level 2 [Member]    
Assets    
Long-term investments, at fair value 0  
Total 0  
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 2 [Member] | National Holdings Corporation [Member]    
Assets    
Total   104
Liabilities    
Liabilities   0
Fair Value, Inputs, Level 2 [Member] | Contingently Issuable Warrant [Member]    
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 2 [Member] | Warrant [Member]    
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 2 [Member] | Helocyte Convertible Note One [Member]    
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 2 [Member] | Avenue Convertible Note [Member]    
Liabilities    
Liabilities 0  
Fair Value, Inputs, Level 2 [Member] | Corporate stock Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   0
Fair Value, Inputs, Level 2 [Member] | Municipal bonds Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   0
Fair Value, Inputs, Level 2 [Member] | Restricted stock Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   104
Fair Value, Inputs, Level 2 [Member] | Corporate stock Liabilities [Member] | National Holdings Corporation [Member]    
Liabilities    
Liabilities   0
Fair Value, Inputs, Level 3 [Member]    
Assets    
Long-term investments, at fair value 746  
Total 746  
Liabilities    
Liabilities 5,186  
Fair Value, Inputs, Level 3 [Member] | National Holdings Corporation [Member]    
Assets    
Total   0
Liabilities    
Liabilities   10,096
Fair Value, Inputs, Level 3 [Member] | Contingently Issuable Warrant [Member]    
Liabilities    
Liabilities 298  
Fair Value, Inputs, Level 3 [Member] | Warrant [Member]    
Liabilities    
Liabilities 104  
Fair Value, Inputs, Level 3 [Member] | Helocyte Convertible Note One [Member]    
Liabilities    
Liabilities 4,580  
Fair Value, Inputs, Level 3 [Member] | Avenue Convertible Note [Member]    
Liabilities    
Liabilities $ 204  
Fair Value, Inputs, Level 3 [Member] | Corporate stock Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   0
Fair Value, Inputs, Level 3 [Member] | Municipal bonds Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   0
Fair Value, Inputs, Level 3 [Member] | Restricted stock Assets [Member] | National Holdings Corporation [Member]    
Assets    
Total   0
Fair Value, Inputs, Level 3 [Member] | Corporate stock Liabilities [Member] | National Holdings Corporation [Member]    
Liabilities    
Liabilities   0
Fair Value, Inputs, Level 3 [Member] | Warrants Issuable [Member] | National Holdings Corporation [Member]    
Liabilities    
Liabilities   $ 10,096