Derivatives - Additional Information (Detail) $ in Thousands		3 Months Ended		9 Months Ended
	Jun. 30, 2020 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2016 USD ($)	Jun. 30, 2016 derivative
Derivative [Line Items]
Interest expense		$ 9,299	$ 15,944	$ 33,431	$ 46,165
Estimated decrease in interest expense	$ (260)
Interest rate swap (cash flow hedge)
Derivative [Line Items]
Available for sale securities pledged for collateral		100,900		100,900		$ 30,000
Notional amount		$ 30,000		30,000
Interest rate swap (cash flow hedge) | Cash Flow Hedging
Derivative [Line Items]
Number of derivatives | derivative								2
Notional amount							$ 30,000
Average interest rate							1.10%
Interest expense				$ 17	$ 334