Common Stock	3 Months Ended
Mar. 31, 2018
Equity [Abstract]
Common Stock	ACM is authorized to issue 100,000,000 shares of Class A common stock and 7,303,533 shares of Class B common stock, each with a par value of $0.0001. Each share of Class A common stock is entitled to one vote, and each share of Class B common stock is entitled to twenty votes and is convertible at any time into one share of Class A common stock. Shares of Class A common stock and Class B common stock are treated equally, identically and ratably with respect to any dividends if declared by the Board of Directors unless the Board of Directors declares different dividends to the Class A common stock and Class B common stock by getting approval from a majority of common stock holders. In August 2017 ACM entered into a securities purchase agreement with PDHTI and its subsidiary Pudong Science and Technology (Cayman) Co., Ltd. (“PST”), in which ACM agreed to bid, in an auction process mandated by PRC regulations, to purchase PDHTI’s 10.78% equity interest in ACM Shanghai and to sell shares of Class A common stock to PST. On September 8, 2017, ACM issued 1,119,576 shares of Class A common stock to PST for a purchase price of $7.50 per share, representing an aggregate purchase price of $8,397. In August 2017 ACM entered into a securities purchase agreement with ZSTVC and its subsidiary Zhangjiang AJ Company Limited (“ZJAJ”), in which ACM agreed to bid, in an auction process mandated by PRC regulations, to purchase ZSTVC’s 7.58% equity interest in ACM Shanghai and to sell shares of Class A common stock to ZJAJ. On September 8, 2017, ACM issued 787,098 shares of Class A common stock to ZJAJ for a purchase price of $7.50 per share, or an aggregate purchase price of $5,903. In September 2017 ACM issued 133,334 shares of Class A common stock to Ninebell for a purchase price of $7.50 per share, or an aggregate purchase price of $1,000 (note 10). In November 2017 ACM issued 2,233,000 shares of Class A common stock and received net proceeds of $11,664 from the IPO and concurrently ACM issued an additional 1,333,334 shares of Class A common stock in a private placement for net proceeds of $7,053. Upon the completion of the IPO on November 2, 2017, the Company issued a five-year warrant (the “Underwriter's Warrant”) to Roth Capital Partners, LLC, the lead underwriter of the IPO, for the purchase of up to 80,000 shares of Class A common stock at an exercise price of $6.16 per share. The Underwriter’s Warrant was immediately exercisable and expires on November 1, 2022. The Underwriter's Warrant is equity classified and its fair value was $137 at the IPO closing date, using the Black Scholes model with the following assumptions: volatility of 28.26%, a dividend rate of 0%, and a risk-free discount rate of 2%. In September 2017 ACM issued 133,334 shares of Class A common stock to Ninebell for a purchase price of $7.50 per share, or an aggregate purchase price of $1,000 (note 10). At various dates during 2017, ACM issued 472,889 shares of Class A common stock for options exercised by certain employee and non-employees. At various dates during the three months ended March 31, 2018, ACM issued 57,222 shares of Class A common stock for options exercised by certain employee and non-employees. On March 30, 2018, SMC exercised its warrant (note 8) and purchased 397,502 shares of Class A common stock. At March 31, 2018 and December 31, 2017, the number of shares of Class A common stock issued and outstanding was 13,390,270 and 12,935,546, respectively. At March 31, 2018 and December 31, 2017, the number of shares of Class B common stock issued and outstanding was 2,409,738.

Common Stock

3 Months Ended

Mar. 31, 2018

ACM is authorized to issue 100,000,000 shares of Class A common stock and 7,303,533 shares of Class B common stock, each with a par value of $0.0001. Each share of Class A common stock is entitled to one vote, and each share of Class B common stock is entitled to twenty votes and is convertible at any time into one share of Class A common stock. Shares of Class A common stock and Class B common stock are treated equally, identically and ratably with respect to any dividends if declared by the Board of Directors unless the Board of Directors declares different dividends to the Class A common stock and Class B common stock by getting approval from a majority of common stock holders.

In August 2017 ACM entered into a securities purchase agreement with PDHTI and its subsidiary Pudong Science and Technology (Cayman) Co., Ltd. (“PST”), in which ACM agreed to bid, in an auction process mandated by PRC regulations, to purchase PDHTI’s 10.78% equity interest in ACM Shanghai and to sell shares of Class A common stock to PST. On September 8, 2017, ACM issued 1,119,576 shares of Class A common stock to PST for a purchase price of $7.50 per share, representing an aggregate purchase price of $8,397.

In August 2017 ACM entered into a securities purchase agreement with ZSTVC and its subsidiary Zhangjiang AJ Company Limited (“ZJAJ”), in which ACM agreed to bid, in an auction process mandated by PRC regulations, to purchase ZSTVC’s 7.58% equity interest in ACM Shanghai and to sell shares of Class A common stock to ZJAJ. On September 8, 2017, ACM issued 787,098 shares of Class A common stock to ZJAJ for a purchase price of $7.50 per share, or an aggregate purchase price of $5,903.

In September 2017 ACM issued 133,334 shares of Class A common stock to Ninebell for a purchase price of $7.50 per share, or an aggregate purchase price of $1,000 (note 10).

In November 2017 ACM issued 2,233,000 shares of Class A common stock and received net proceeds of $11,664 from the IPO and concurrently ACM issued an additional 1,333,334 shares of Class A common stock in a private placement for net proceeds of $7,053.

Upon the completion of the IPO on November 2, 2017, the Company issued a five-year warrant (the “Underwriter's Warrant”) to Roth Capital Partners, LLC, the lead underwriter of the IPO, for the purchase of up to 80,000 shares of Class A common stock at an exercise price of $6.16 per share. The Underwriter’s Warrant was immediately exercisable and expires on November 1, 2022. The Underwriter's Warrant is equity classified and its fair value was $137 at the IPO closing date, using the Black Scholes model with the following assumptions: volatility of 28.26%, a dividend rate of 0%, and a risk-free discount rate of 2%.

In September 2017 ACM issued 133,334 shares of Class A common stock to Ninebell for a purchase price of $7.50 per share, or an aggregate purchase price of $1,000 (note 10).

At various dates during 2017, ACM issued 472,889 shares of Class A common stock for options exercised by certain employee and non-employees. At various dates during the three months ended March 31, 2018, ACM issued 57,222 shares of Class A common stock for options exercised by certain employee and non-employees.

On March 30, 2018, SMC exercised its warrant (note 8) and purchased 397,502 shares of Class A common stock.

At March 31, 2018 and December 31, 2017, the number of shares of Class A common stock issued and outstanding was 13,390,270 and 12,935,546, respectively. At March 31, 2018 and December 31, 2017, the number of shares of Class B common stock issued and outstanding was 2,409,738.