Goodwill (Tables)
 6 Months Ended
Jan. 31, 2016
Goodwill [Abstract]  
Schedule of goodwill by segment
The carrying amount of goodwill by segment as of January 31, 2016 and July 31, 2015 are as follows:
 
 
Telecommunications
Transmission
 
RF Microwave
Amplifiers
 
Mobile Data
Communications
 
Total
Goodwill
 
$
107,779,000

 
29,575,000

 
13,249,000

 
$
150,603,000

Accumulated impairment
 
—

 
—

 
(13,249,000
)
 
(13,249,000
)
Balance
 
$
107,779,000

 
29,575,000

 
—

 
$
137,354,000