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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Expiration date of each operating loss carryforward included in operating loss carryforward, in YYYY-MM-DD format.

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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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The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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Expiration date of the tax credit carryforward, in YYYY-MM-DD format.

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Amount of unrecognized tax benefits.

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Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

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Income Taxes (Narrative) (Details) - USD ($)	12 Months Ended
Income Taxes (Narrative) (Details) - USD ($)	Dec. 31, 2022	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Operating Loss Carryforwards [Line Items]
U.S federal corporate tax rate	21.00%	21.00%	21.00%
Valuation allowance increase (decrease)	$ 17,800,000	$ 7,700,000
Unrecognized tax benefits	6,496,000	$ 5,001,000	$ 4,500,000	$ 4,400,000
Unrecognized tax benefits no significant change over next 12 months	0
Federal [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	133,400,000
Federal [Member] \| Expires Between 2029 And 2037 [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	74,100,000
Federal [Member] \| Indefinitely [Member]
Operating Loss Carryforwards [Line Items]
Net operating loss carryforwards	43,900,000
Federal [Member] \| Expires Between 2024 And 2042 [Member] \| Research And Development Tax Credit Carryforward [Member]
Operating Loss Carryforwards [Line Items]
Research and development tax credits	$ 16,100,000
Federal [Member] \| Minimum [Member] \| Expires Between 2029 And 2037 [Member]
Operating Loss Carryforwards [Line Items]
Expiration date of pre-tax net operating loss carryforwards	Jan. 01, 2029
Federal [Member] \| Minimum [Member] \| Expires Between 2024 And 2042 [Member] \| Research And Development Tax Credit Carryforward [Member]
Operating Loss Carryforwards [Line Items]
Expiration date of federal research and development tax credits	Jan. 01, 2024
Federal [Member] \| Maximum [Member] \| Expires Between 2029 And 2037 [Member]
Operating Loss Carryforwards [Line Items]
Expiration date of pre-tax net operating loss carryforwards	Dec. 31, 2037
Federal [Member] \| Maximum [Member] \| Expires Between 2024 And 2042 [Member] \| Research And Development Tax Credit Carryforward [Member]
Operating Loss Carryforwards [Line Items]
Expiration date of federal research and development tax credits	Dec. 31, 2042