Carrying amount as of the balance sheet date of cash collateral held for borrowed securities, for which the cash is restricted as to withdrawal or usage.

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Amount after tax of increase (decrease) to equity or (increase) decrease to net assets, resulting from the cumulative effect adjustment of a new accounting principle applied in the period of adoption.

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Amount of cash restricted as to withdrawal or usage. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Amount of cash restricted as to withdrawal or usage, classified as noncurrent. Cash includes, but is not limited to, currency on hand, demand deposits with banks or financial institutions, and other accounts with general characteristics of demand deposits.

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Summary of Significant Accounting Policies (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Mar. 31, 2019	Jan. 01, 2019	Dec. 31, 2018	Jan. 01, 2018
Restricted cash for the benefit of the landlords of leased properties	$ 1,700			$ 1,800
Restricted cash to collateralize corporate credit card				500
Restricted cash (non-current)	$ 1,735			1,735
Restricted cash (current)				$ 622
Change in fair value of the unvested awards					$ 100
ASU 2016-02
Change in fair value of the unvested awards		$ 800
Accumulated deficit \| ASU 2016-02
Change in fair value of the unvested awards		$ 800	$ 800