Condensed Consolidated Statements of Convertible Preferred Stock and Stockholders’ Deficit - USD ($) | Common Stock | Additional Paid-in capital | Accumulated other comprehensive loss | Accumulated deficit | Series A convertible preferred stock | Series B convertible preferred stock | Series C convertible preferred stock | Total |
Temporary equity, beginning balance at Dec. 31, 2018 | | | | | $ 6,483,044 | $ 49,742,942 | $ 56,364,645 | |
Temporary Equity, Beginning Balance (in shares) at Dec. 31, 2018 | | | | | 612,446 | 7,235,969 | 4,712,698 | |
Increase (Decrease) in Temporary Equity | | | | | | | | |
Issuance of convertible preferred stock, net of issuance costs | | | | | | | $ 5,598,362 | |
Issuance of convertible preferred stock (in shares) | | | | | | | 467,179 | |
Temporary equity, ending balance at Mar. 31, 2019 | | | | | $ 6,483,044 | $ 49,742,942 | $ 61,963,007 | |
Temporary Equity, Ending Balance (in shares) at Mar. 31, 2019 | | | | | 612,446 | 7,235,969 | 5,179,877 | |
Equity, beginning balance at Dec. 31, 2018 | $ 127,091 | $ 19,666,588 | $ (8,761,325) | $ (62,468,456) | | | | $ (51,436,102) |
Equity, beginning balance (in shares) at Dec. 31, 2018 | 1,155,366 | | | | | | | |
Increase (Decrease) in Stockholders' Equity | | | | | | | | |
Exercise of stock options | $ 2,883 | 20,235 | | | | | | 23,118 |
Exercise of stock options (in shares) | 26,207 | | | | | | | |
Stock‑based compensation | | 97,946 | | | | | | 97,946 |
Foreign currency translation | | | (2,031,175) | | | | | (2,031,175) |
Net loss | | | | (3,475,202) | | | | (3,475,202) |
Equity, ending balance at Mar. 31, 2019 | $ 129,974 | 19,784,769 | (10,792,500) | (65,943,658) | | | | (56,821,415) |
Equity, ending balance (in shares) at Mar. 31, 2019 | 1,181,573 | | | | | | | |
Temporary equity, beginning balance at Dec. 31, 2018 | | | | | $ 6,483,044 | $ 49,742,942 | $ 56,364,645 | |
Temporary Equity, Beginning Balance (in shares) at Dec. 31, 2018 | | | | | 612,446 | 7,235,969 | 4,712,698 | |
Temporary equity, ending balance at Jun. 30, 2019 | | | | | $ 6,483,044 | $ 49,742,942 | $ 61,963,007 | |
Temporary Equity, Ending Balance (in shares) at Jun. 30, 2019 | | | | | 612,446 | 7,235,969 | 5,179,877 | |
Equity, beginning balance at Dec. 31, 2018 | $ 127,091 | 19,666,588 | (8,761,325) | (62,468,456) | | | | (51,436,102) |
Equity, beginning balance (in shares) at Dec. 31, 2018 | 1,155,366 | | | | | | | |
Increase (Decrease) in Stockholders' Equity | | | | | | | | |
Foreign currency translation | | | | | | | | (1,986,667) |
Net loss | | | | | | | | (8,737,650) |
Equity, ending balance at Jun. 30, 2019 | $ 129,974 | 19,971,732 | (10,747,992) | (71,206,106) | | | | (61,852,392) |
Equity, ending balance (in shares) at Jun. 30, 2019 | 1,181,573 | | | | | | | |
Temporary equity, beginning balance at Mar. 31, 2019 | | | | | $ 6,483,044 | $ 49,742,942 | $ 61,963,007 | |
Temporary Equity, Beginning Balance (in shares) at Mar. 31, 2019 | | | | | 612,446 | 7,235,969 | 5,179,877 | |
Temporary equity, ending balance at Jun. 30, 2019 | | | | | $ 6,483,044 | $ 49,742,942 | $ 61,963,007 | |
Temporary Equity, Ending Balance (in shares) at Jun. 30, 2019 | | | | | 612,446 | 7,235,969 | 5,179,877 | |
Equity, beginning balance at Mar. 31, 2019 | $ 129,974 | 19,784,769 | (10,792,500) | (65,943,658) | | | | (56,821,415) |
Equity, beginning balance (in shares) at Mar. 31, 2019 | 1,181,573 | | | | | | | |
Increase (Decrease) in Stockholders' Equity | | | | | | | | |
Stock‑based compensation | | 186,963 | | | | | | 186,963 |
Foreign currency translation | | | 44,508 | | | | | 44,508 |
Net loss | | | | (5,262,448) | | | | (5,262,448) |
Equity, ending balance at Jun. 30, 2019 | $ 129,974 | 19,971,732 | (10,747,992) | (71,206,106) | | | | (61,852,392) |
Equity, ending balance (in shares) at Jun. 30, 2019 | 1,181,573 | | | | | | | |
Equity, beginning balance at Dec. 31, 2019 | $ 21,023 | 226,284,548 | (11,533,778) | (90,528,263) | | | | 124,243,530 |
Equity, beginning balance (in shares) at Dec. 31, 2019 | 21,022,752 | | | | | | | |
Increase (Decrease) in Stockholders' Equity | | | | | | | | |
Exercise of stock options | $ 32 | 29,491 | | | | | | 29,523 |
Exercise of stock options (in shares) | 32,090 | | | | | | | |
Stock‑based compensation | | 905,471 | | | | | | 905,471 |
Foreign currency translation | | | (2,424,653) | | | | | (2,424,653) |
Net loss | | | | (9,400,257) | | | | (9,400,257) |
Equity, ending balance at Mar. 31, 2020 | $ 21,055 | 227,219,510 | (13,958,431) | (99,928,520) | | | | 113,353,614 |
Equity, ending balance (in shares) at Mar. 31, 2020 | 21,054,842 | | | | | | | |
Equity, beginning balance at Dec. 31, 2019 | $ 21,023 | 226,284,548 | (11,533,778) | (90,528,263) | | | | 124,243,530 |
Equity, beginning balance (in shares) at Dec. 31, 2019 | 21,022,752 | | | | | | | |
Increase (Decrease) in Stockholders' Equity | | | | | | | | |
Foreign currency translation | | | | | | | | (667,870) |
Net loss | | | | | | | | (25,768,184) |
Equity, ending balance at Jun. 30, 2020 | $ 21,187 | 228,597,264 | (12,201,648) | (116,296,447) | | | | 100,120,356 |
Equity, ending balance (in shares) at Jun. 30, 2020 | 21,186,827 | | | | | | | |
Equity, beginning balance at Mar. 31, 2020 | $ 21,055 | 227,219,510 | (13,958,431) | (99,928,520) | | | | 113,353,614 |
Equity, beginning balance (in shares) at Mar. 31, 2020 | 21,054,842 | | | | | | | |
Increase (Decrease) in Stockholders' Equity | | | | | | | | |
Exercise of stock options | $ 132 | 121,294 | | | | | | 121,426 |
Exercise of stock options (in shares) | 131,985 | | | | | | | |
Stock‑based compensation | | 1,256,460 | | | | | | 1,256,460 |
Foreign currency translation | | | 1,756,783 | | | | | 1,756,783 |
Net loss | | | | (16,367,927) | | | | (16,367,927) |
Equity, ending balance at Jun. 30, 2020 | $ 21,187 | $ 228,597,264 | $ (12,201,648) | $ (116,296,447) | | | | $ 100,120,356 |
Equity, ending balance (in shares) at Jun. 30, 2020 | 21,186,827 | | | | | | | |