Noncontrolling Interests Income Attributable to NCI Reconciliation Schedule (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017
Noncontrolling Interest [Line Items]
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	$ 28,029	$ 42,872	$ 52,050
Net Income (Loss) Attributable to Noncontrolling Interest	36,442	51,275	59,447
Royce [Member]
Noncontrolling Interest [Line Items]
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest	$ 8,413	$ 8,403	$ 7,397