Leases - Lease Cost and Supplemental Cash Flow Information Related to Leases (Details) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Leases [Abstract]
Operating lease cost	$ 302		$ 848
Operating lease cost		$ 251		$ 708
Total lease cost	302		848
Total lease cost		$ 251		$ 708
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$ 569		$ 1,115

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- Definition

Amount of rent expense incurred for leased assets, including but not limited to, furniture and equipment, that is not directly or indirectly associated with the manufacture, sale or creation of a product or product line.

+ References

No definition available.

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- Definition

Amount of lease cost recognized by lessee for lease contract.

+ References

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- Definition

Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability.

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- Definition

Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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- Definition

Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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