Commitments and Contingencies - Future Minimum Contractual Commitments under Non-cancelable Agreements (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Operating Leased Assets [Line Items]
2021	$ 791
2022	696
2023	596
2024	605
Thereafter	152
Gas Contract
Operating Leased Assets [Line Items]
2020	1,647
2021	680
2022	0
2023	0
2024	0
Thereafter	0
Office Leases
Operating Leased Assets [Line Items]
2020	632
2021	791
2022	696
2023	596
2024	605
Thereafter	152
Automobile Leases
Operating Leased Assets [Line Items]
2020	219
2021	84
2022	5
2023	0
2024	0
Thereafter	0
Non-Cancelable Agreement
Operating Leased Assets [Line Items]
2020	2,498
2021	1,555
2022	701
2023	596
2024	605
Thereafter	$ 152

Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in next fiscal year following latest fiscal year.

+ References

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fifth fiscal year following latest fiscal year.

+ References

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

+ References

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in third fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in second fiscal year following latest fiscal year.

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+ References

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