Investments - Summary of Selected Financial Information for JCP Fund V (Details) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended			12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Nov. 30, 2020	Nov. 30, 2019	Nov. 30, 2018
Schedule of Equity Method Investments [Line Items]
Total assets							$ 47,751,997	$ 43,516,115
Total liabilities							41,385,865	37,386,368
JCP Fund V
Schedule of Equity Method Investments [Line Items]
Net gains (losses) from our investments in JCP Fund V							$ (3,000)	$ (5,700)	$ 12,100
Total assets				$ 49,404	$ 63,248
Total liabilities				84	76
Total partners’ capital				49,319	63,172
Net increase (decrease) in net assets resulting from operations	$ (1,397)	$ (8,412)	$ 19,712	$ (12,456)	$ (19,070)	$ 15,252