Revolving Credit Facility (Details) - Line of Credit - USD ($)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Dec. 31, 2020	Sep. 30, 2020	Mar. 31, 2020	Dec. 31, 2019
Line of Credit Facility [Line Items]
Weighted average interest rate	3.25%				2.64%
Allowable indebtedness for acquisition				$ 36,000,000.0
Revolving Credit Facility
Line of Credit Facility [Line Items]
Credit facility, borrowing capacity			$ 100,000,000.0
Line of credit facility, remaining borrowing capacity	$ 91,900,000		66,000,000.0
Commitment fee	200,000	$ 100,000
Deferred financing costs incurred						$ 600,000
Deferred financing costs net of accumulated amortization	$ 400,000		$ 400,000
Letter of Credit
Line of Credit Facility [Line Items]
Letter of credit		$ 15,000,000.0		$ 40,000,000.0
Letter of Credit | Minimum
Line of Credit Facility [Line Items]
Commitment fee percentage	0.15%
Letter of Credit | Maximum
Line of Credit Facility [Line Items]
Commitment fee percentage	0.30%