Balance Sheet Account Detail - Prepaid Expenses (Details) - USD ($) $ in Thousands	Mar. 31, 2019	Dec. 31, 2018
Organization, Consolidation and Presentation of Financial Statements [Abstract]
Deposits and other	$ 6,760	$ 6,792
Value of equity forward-sale contract (see Note 7)	793	0
Prepaid insurance	402	782
Prepaid expenses and other assets	$ 7,955	$ 7,574

Equity Securities FV-NI, Current

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The carrying amount of the asset transferred to a third party to serve as a deposit, which typically serves as security against failure by the transferor to perform under terms of an agreement.

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Amount of asset related to consideration paid in advance for other costs that provide economic benefits within a future period of one year or the normal operating cycle, if longer.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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