Investment Information - Limited partnership interests (Details) - USD ($) $ in Thousands		Jun. 30, 2022	Dec. 31, 2021
Schedule of Equity Method Investments [Line Items]
Maximum Exposure to Loss		$ 3,625,167	$ 3,248,206
Aggregate unfunded commitments		3,500,000	3,000,000
Equity method investments
Schedule of Equity Method Investments [Line Items]
Maximum Exposure to Loss	[1]	3,496,341	3,077,611
Aggregate unfunded commitments		3,000,000	2,600,000
Fair value option
Schedule of Equity Method Investments [Line Items]
Maximum Exposure to Loss	[2]	128,826	170,595
Aggregate unfunded commitments		$ 21,700	$ 18,800

[1] Aggregate unfunded commitments were $3.0 billion at June 30, 2022, compared to $2.6 billion at December 31, 2021.

[2] Aggregate unfunded commitments were $21.7 million at June 30, 2022, compared to $18.8 million at December 31, 2021.