Subsequent Events (Details) - Subsequent Event $ / shares in Units, $ in Thousands	Feb. 03, 2019 USD ($) $ / shares shares
Subsequent Event [Line Items]
Number of business days following Tesla filing date	4 days
Number of months from offer before termination	5 months
Maxwell Technologies, Inc.
Subsequent Event [Line Items]
Share price (in dollars per share)	$ 4.75
Number of Tesla shares at volume weighted average closing sale price \| shares	1
Number of trading days used to determine trading price	5 days
Tesla Trading Price (equal to or less than)	$ 245.90
Exchange ratio	0.0193
Termination fee \| $	$ 8,295

Business Acquisition, Number of Prevailing Trading Days used to Determine Share Price

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- Definition

Business Combination, Acquirer Trading Price, Maximum

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- Definition

Business Combination, Number of Months From Offer Before Termination

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- Definition

Business Combination, Share Exchange Ratio

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- Definition

Business Combination, Termination Fee to be Paid to Acquirer per Agreement if Acquisition is Unapproved

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- Definition

Maximum Number of Days Following Reporting Date

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- Definition

Number of Acquiring Company Shares Received Per Share Price

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- Definition

Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

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