Term of lessee's operating leases' options to extend.

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease having initial or remaining lease term in excess of one year to be paid in remainder of current fiscal year.

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Amount of lessee's undiscounted obligation for lease payments in excess of discounted obligation for lease payments for operating lease.

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Remaining lease term of operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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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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Present value of lessee's discounted obligation for lease payments from operating lease.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Indicates line item in statement of financial position that includes current operating lease liability.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Indicates line item in statement of financial position that includes noncurrent operating lease liability.

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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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Amount of lessee's right to use underlying asset under operating lease.

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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Leases (Details) - USD ($)	3 Months Ended		9 Months Ended
Leases (Details) - USD ($)	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease with Options to Extend Lease, Term			5 years
Lease expense
Operating lease cost	$ 357,000	$ 358,000	$ 1,072,000	$ 1,073,000
Operating Leases:
Operating lease right of use assets	3,506,000		3,506,000		$ 4,484,000
Current operating lease liabilities	$ (843,000)		$ (843,000)		(1,304,000)
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List]	Other Accrued Liabilities, Current		Other Accrued Liabilities, Current
Noncurrent operating lease liabilities	$ (2,602,000)		$ (2,602,000)		(3,119,000)
Operating Lease, Liability, Noncurrent, Statement of Financial Position [Extensible List]	Other non-current liabilities		Other non-current liabilities
Total operating lease liabilities	$ 3,445,000		$ 3,445,000		$ 4,423,000
Weighted average remaining lease term (in years), Operating leases	3 years 6 months		3 years 6 months		4 years
Weighted average discount rate, Operating leases	5.00%		5.00%		4.90%
Cash paid for amounts included in the measurement of lease liabilities
Operating cash flows from operating leases			$ 1,072,000	$ 1,073,000
Maturities of lease liabilities
2020 (remainder of year)	$ 358,000		358,000		$ 1,433,000
2021	1,174,000		1,174,000		1,174,000
2022	1,102,000		1,102,000		1,102,000
2023	1,000,000		1,000,000		1,000,000
2024	530,000		530,000		530,000
Total lease payments	4,164,000		4,164,000		5,239,000
Less: imputed interest	(719,000)		(719,000)		(816,000)
Total operating lease liabilities	$ 3,445,000		$ 3,445,000		$ 4,423,000
Minimum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Remaining Lease Term	1 year		1 year
Maximum [Member]
Lessee, Lease, Description [Line Items]
Lessee, Operating Lease, Remaining Lease Term	4 years		4 years