Other Assets and Liabilities - Additional Information (Detail)		3 Months Ended
	Jan. 01, 2020 USD ($)	Mar. 31, 2020 USD ($) Loans	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
CECL reserve		$ 112,694,000	$ 112,694,000
Increase in current expected credit loss reserve		$ 122,702,000
Number of loans receivable | Loans		94
Credit Loss Reserve [Member]
CECL reserve		$ 5,100,000
Unfunded Loan Commitments [Member]
CECL reserve		22,536,000		$ 0
Increase in current expected credit loss reserve	$ 19.3	$ 19,273,000
Number of loans receivable | Loans		94
Unfunded loan commitments		$ 3,900,000
Held To Maturity Debt Securities [Member]
CECL reserve		5,122,000	0
Increase in current expected credit loss reserve		4,677,000
Accounting Standards Update 2016-13 [Member]
CECL reserve		17,650,000
Accounting Standards Update 2016-13 [Member] | Unfunded Loan Commitments [Member]
CECL reserve		3,263,000	$ 3,263,000
Increase in current expected credit loss reserve		22.5
Accounting Standards Update 2016-13 [Member] | Held To Maturity Debt Securities [Member]
Increase in current expected credit loss reserve		$ 445,000