Real Estate and Other Investments - Assets and Liabilities Related to VIEs (Detail) - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Variable Interest Entity [Line Items]
Investment real estate	$ 551,219	$ 587,516
Short-term investments	425,321	206,760
Cash and cash equivalents	452,001	268,164
Other assets	171,285	163,222
Notes payable	157,997	137,963
Other liabilities	446,882	452,985
VIE, Primary Beneficiary
Variable Interest Entity [Line Items]
Investment real estate	134,534	141,843
Short-term investments	500	500
Cash and cash equivalents	11,155	10,392
Other receivables	3,673	3,939
Other assets	15,355	13,231
Total assets of consolidated VIEs	165,217	169,905
Notes payable	157,997	137,963
Other liabilities	9,731	7,145
Total liabilities of consolidated VIEs	$ 167,728	$ 145,108