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Income Taxes (Income Tax Provision (benefit) Reconciliation) (Details) - USD ($) $ in Thousands | 12 Months Ended
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Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Income Tax Disclosure [Abstract] |  |  |
Tax provision at statutory U.S. federal income tax rate | $ (9,117) | $ 13,193 | $ 18,121
State income tax — net of federal income tax benefit | (3,952) | 2,144 | 3,124
Adjustment to deferred tax depreciation |  | (1,414) |
Stock based compensation | (414) | (1,318) | (1,212)
Nondeductible officer compensation | 244 | 1,195 | 1,212
Research and development tax credits | (518) | (642) | (674)
Changes in valuation allowance | 4,365 |  |
Other | 32 | 233 | (384)
Income tax provision (benefit) | $ (9,360) | $ 13,391 | $ 20,187

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- Definition Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 12 -URI https://asc.fasb.org/extlink&oid=121826272&loc=d3e32687-109319 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 718 -SubTopic 740 -Section 35 -Paragraph 2 -URI https://asc.fasb.org/extlink&oid=126970579&loc=d3e23163-113944 + Details
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