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Long‑Term Debt - Narrative (Details) - USD ($)	Sep. 30, 2021	Dec. 31, 2020	Apr. 02, 2020
Interest Rate Swap \| Not Designated as Hedging Instrument
Debt Instrument [Line Items]
Derivative notional amount			$ 200,000,000
Derivative fair value	$ 9,545,000	$ 347,000
Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Effective interest rate			0.73%