Significant Accounting Policies - Revenue Recognition (Narrative) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2024	Dec. 31, 2023	Mar. 31, 2023
Deferred Revenue Arrangement By Type Table [Line Items]
Days past due for income recognition on debt and preferred equity investments to be suspended	90 days
Deferred revenue	$ 157,756	$ 134,053
Unused and Unexpired Tickets
Deferred Revenue Arrangement By Type Table [Line Items]
Deferred revenue	$ 4,200		$ 3,200