Income Taxes - Income Taxes Paid (Net of Refunds) (Details) $ in Thousands	12 Months Ended
Dec. 31, 2025 USD ($)
Income Taxes
Total	$ 46
Massachusetts
Income Taxes
State	37
New Hampshire
Income Taxes
State	5
All other states
Income Taxes
State	$ 4

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Amount, after income tax refund received, of cash paid to state and local tax jurisdictions for tax on income.

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Amount, after refund, of cash paid to foreign, federal, state, and local jurisdictions as income tax.

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