Revenue Recognition (Revenue disaggregated by timing of revenue recognition) (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2024	Jun. 30, 2023
Revenues [Abstract]
Total revenues	$ 1,548,490	$ 1,540,308
Insurance premium revenues recognized under ASC 944
Revenues [Abstract]
Total revenues	43,148	44,492
Net investment and interest income recognized under other topics
Revenues [Abstract]
Total revenues	37,125	64,592
Revenues recognized under ASC 842
Revenues [Abstract]
Total revenues	1,254,317	1,222,316
Revenues recognized under ASC 606
Revenues [Abstract]
Total revenues	213,900	208,908
Revenues recognized over time:
Revenues [Abstract]
Total revenues	100,175	91,315
Revenues recognized at a point in time:
Revenues [Abstract]
Total revenues	$ 113,725	$ 117,593