Stockholders' Equity, Convertible Preferred Stock and Redeemable Non-controlling Interest (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance			$ 7,485
Loss attributable to non-controlling interest	$ (244)	$ (437)	(611)	$ (737)
Ending balance	0		0
Qingdao Xingyang City Investment
Stockholders' Equity Attributable to Noncontrolling Interest [Roll Forward]
Beginning balance			7,485	0
Initial investment			0	7,047
Accretion of dividend			347	323
Loss attributable to non-controlling interest			(195)	(79)
Adjustment to redemption value			195	79
Ending balance	$ 7,832	$ 7,370	$ 7,832	$ 7,370

Amount of increase in noncontrolling interest from accretion of dividend.

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Change in noncontrolling interest during the period as a result of a change in the redemption value of redeemable noncontrolling interest.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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Amount of increase in noncontrolling interest from subsidiary issuance of equity interests to noncontrolling interest holders.

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As of the reporting date, the aggregate carrying amount of all noncontrolling interests which are redeemable by the (parent) entity (1) at a fixed or determinable price on a fixed or determinable date, (2) at the option of the holder of the noncontrolling interest, or (3) upon occurrence of an event that is not solely within the control of the (parent) entity. This item includes noncontrolling interest holder's ownership (or holders' ownership) regardless of the type of equity interest (common, preferred, other) including all potential organizational (legal) forms of the investee entity.

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