Taxes (Narrative) (Details) $ in Thousands, £ in Millions	12 Months Ended
Dec. 31, 2022 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2022 GBP (£)
Taxes
Income tax credits	$ 4,700	$ 3,800
Income tax credits - UK research and development	4,719	3,849
Income tax benefit	(4,717)	(3,847)
Valuation allowance for deferred tax assets	53,306	56,730
Increase in valuation allowance	3,400
Federal
Taxes
NOLs carryforward	3,600	2,500
State
Taxes
NOLs carryforward	$ 22,100	21,100
Operating loss carryforward, expiration date	Dec. 31, 2028
Foreign
Taxes
NOLs carryforward	$ 203,000	$ 218,500
Percentage of tax rate adopted in respect of deferred tax assets measurement	50.00%
Annual NOL allowance restriction \| £			£ 5

Represents the percentage of tax rate adopted in respect of deferred tax assets measurement.

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Amount of current foreign income tax expense (benefit) pertaining to income (loss) from continuing operations.

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Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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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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The portion of the valuation allowance pertaining to the deferred tax asset representing potential future taxable deductions from net operating loss carryforwards for which it is more likely than not that a tax benefit will not be realized.

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

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