Long-term Debt, Line of Credit and Derivatives - Provisions of 364-Day Revolving Credit Facility (Details) - 364-Day Revolving Credit Facility - Line of Credit - USD ($)	Jun. 08, 2020	Jun. 30, 2020
Debt Instrument [Line Items]
Credit facility term	364 days
Line of credit facility, maximum borrowing capacity	$ 20,000,000.0
Minimum borrowing increment amount	1,000,000.0
Increment borrowing multiple for amounts borrowed in excess of minimum borrowing amount	$ 250,000
Amount outstanding		$ 0
Remaining borrowing capacity		$ 20,000,000.0