Quarterly report pursuant to Section 13 or 15(d)

Liquidity (Details)

v3.19.2
Liquidity (Details) - USD ($)
Jun. 30, 2019
May 22, 2019
Mar. 31, 2019
Jun. 30, 2018
Mar. 31, 2018
May 23, 2017
Debt Instrument [Line Items]            
Cash $ 16,387,000   $ 11,059,000 $ 8,969,000 $ 13,051,000  
Credit Agreement | Western Alliance Bank            
Debt Instrument [Line Items]            
Credit agreement, total facility amount   $ 20,000,000       $ 5,000,000