Derivative Financial Instruments - Interest Rate Swaps (Additional Information) (Details)	3 Months Ended		6 Months Ended
	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Jun. 30, 2020 USD ($)	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Jul. 31, 2015 agreement
Credit Derivatives [Line Items]
Gain (loss) on derivative | $	$ 400,000	$ (500,000)	$ (700,000)	$ (1,100,000)
Interest rate swap
Credit Derivatives [Line Items]
Gain (loss) on derivative | $	37,000	48,000	74,000	95,000
Cash flow hedging | Interest rate swap | PPA Company V
Credit Derivatives [Line Items]
Number of swap agreements entered into | agreement						9
Derivative, notional amount | $	183,200,000		183,200,000		$ 184,200,000
Gain (loss) on derivative | $	$ (35,600)	$ 36,000	$ (71,000)	$ 12,000
Cash flow hedging | Interest rate swap maturing In 2016 | PPA Company V
Credit Derivatives [Line Items]
Number of swap agreements entered into | agreement						3
Cash flow hedging | Interest rate swap maturing September 30, 2031 | PPA Company V
Credit Derivatives [Line Items]
Number of swap agreements entered into | agreement						3
Cash flow hedging | Interest rate swap maturing December 21, 2021 | PPA Company V
Credit Derivatives [Line Items]
Number of swap agreements entered into | agreement						3