The amount of expense recognized in the current period that reflects the allocation of the cost of tangible assets over the assets' useful lives. Includes production and non-production related depreciation.

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Amount of increase (decrease) of long-lived, physical assets used in the normal conduct of business and not intended for resale. Examples include, but are not limited to, land, buildings, machinery and equipment, office equipment, furniture and fixtures, and computer equipment.

+ References

No definition available.

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- Definition

The amount of accumulated depreciation, by major property class, recorded on property subject to or available for lease as of the balance sheet date.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 20
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- Definition

Amount before accumulated depreciation of physical assets used in the normal conduct of business to produce goods and services subject to or available for lease.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Balance Sheet Components - Property Plant and Equipment, Net (Additional Information) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018
Property Subject to or Available for Operating Lease [Line Items]
Depreciation and Amortization	$ 11,271	$ 10,847
Property subject to operating lease
Property Subject to or Available for Operating Lease [Line Items]
Property, plant and equipment	397,500		$ 397,500
Accumulated depreciation	83,800		$ 77,400
Construction in progress
Property Subject to or Available for Operating Lease [Line Items]
Decrease in property plant and equipment	18,600
Property, Plant and Equipment
Property Subject to or Available for Operating Lease [Line Items]
Depreciation and Amortization	$ 6,400	$ 6,400