Commitments and contingencies (Details Textual) |
3 Months Ended |
---|---|
Mar. 31, 2019
USD ($)
| |
Commitments and Contingencies [Line Items] | |
Estimated Litigation Liability | $ 6,200,000 |
Litigation Settlement, Expense | $ 275,000 |
Interest Rate Description Litigation | plus legal interest that accrued at 12% per annum from August 13, 2008 to June 30, 2013, and thereafter accrued and continues to accrue at 6% per annum |