Commitments and Contingencies (Narrative) (Details)	12 Months Ended
Dec. 31, 2018 USD ($) ft²	Dec. 31, 2017 USD ($)
Loss Contingencies [Line Items]
Rent expense	$ 1,000,000	$ 1,000,000
Future minimum lease payments due in 2018	1,000,000
Future minimum lease payments due in 2019	1,000,000
Future minimum lease payments due in 2020	1,000,000
Future minimum lease payments due in 2021	1,000,000
Future minimum lease payments due in 2022	1,000,000
Future minimum lease payments due in 2023	1,000,000
Future minimum lease payments due in 2024	1,000,000
Equipment purchases commitments	$ 800,000
Contribution limitation to percentage of compensation	15.00%
Employer contributions	$ 0	$ 0
Hopewell Junction, New York [Member]
Loss Contingencies [Line Items]
Area of leased real estate property \| ft²	42,000
Lease expiration date	May 01, 2024
Santa Clara, California [Member]
Loss Contingencies [Line Items]
Area of leased real estate property \| ft²	2,000
Lease expiration date	Oct. 01, 2019

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