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Decrease in noncontrolling interest balance from payment of dividends or other distributions by the non-wholly owned subsidiary or partially owned entity, included in the consolidation of the parent entity, to the noncontrolling interest holders.

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Aggregate amount of cumulative preferred dividends in arrears.

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Noncontrolling Interests Rollforward (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016	May 02, 2017
Noncontrolling Interest [Line Items]
Preferred Stock, Amount of Preferred Dividends in Arrears	$ 981
Redeemable Noncontrolling Interest, Equity, Carrying Amount	692,376	$ 732,295	$ 677,772	$ 175,785
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	28,029	42,872	52,050
Proceeds from (Payments to) Noncontrolling Interests	(22,193)	57,228	(44,587)
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	(1,325)		5,986
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(15,547)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	29,815	53,388	29,461
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			508,817		$ 105,300
Noncontrolling Interest, Period Increase (Decrease), Foreign Exchange	(4,738)	381	(153)
RE Reclassified for MEP Amortization	18,015	7,430	9,335
Noncontrolling Interest, Change in Redemption Value	(12,345)
CIVs and Other
Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	103,630	125,047	58,470	94,136
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	776	6,656	11,452
Proceeds from (Payments to) Noncontrolling Interests	(22,193)	59,921	(47,118)
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	0		0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	0	0	0
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			0
Noncontrolling Interest, Period Increase (Decrease), Foreign Exchange	0	0	0
RE Reclassified for MEP Amortization	0	0	0
Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	540,595	573,950	591,254	68,922
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	27,253	36,216	40,598	40,598
Proceeds from (Payments to) Noncontrolling Interests	0	(2,693)	2,531
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	0		0
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	29,815	53,388	29,461	29,461
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			508,817
Noncontrolling Interest, Period Increase (Decrease), Foreign Exchange	(4,738)	381	(153)	(153)
RE Reclassified for MEP Amortization	1,837	2,180	0
Noncontrolling Interest, Change in Redemption Value	1,837	2,180
Management Equity Plan [Member]
Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	48,151	33,298	28,048	12,727
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	0	0	0
Proceeds from (Payments to) Noncontrolling Interests		0
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	(1,325)		5,986
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	0	0	0
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			0
Noncontrolling Interest, Period Increase (Decrease), Foreign Exchange	0	0	0
RE Reclassified for MEP Amortization	16,178	5,250	9,335
EnTrustPermal [Member] \| Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	380,684	386,884	404,852
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	9,735	19,709		22,146
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(15,935)	37,677		20,494
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			403,200
Noncontrolling Interest, Period Increase (Decrease), Foreign Exchange	0
Noncontrolling Interest, Change in Redemption Value	0
Clarion Partners [Member] \| Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	123,502	117,272	113,173
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	16,127	13,172		12,171
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(11,734)	11,253		4,298
Noncontrolling Interest, Period Increase (Decrease), Foreign Exchange	0
Noncontrolling Interest, Change in Redemption Value	1,837	2,180
RARE Infrastructure, Ltd [Member]
Noncontrolling Interest [Line Items]
Preferred Stock, Amount of Preferred Dividends in Arrears	2,362
RARE Infrastructure, Ltd [Member] \| Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	35,181	68,285	68,747	67,155
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	1,660	3,474		5,742
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(2,134)	4,317		3,997
Business Combination, Acquisition of Less than 100 Percent, Noncontrolling Interest, Fair Value			105,300
Noncontrolling Interest, Period Increase (Decrease), Foreign Exchange	(4,738)	381		(153)
Noncontrolling Interest, Change in Redemption Value	0
Royce [Member]
Noncontrolling Interest [Line Items]
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest	8,413	8,403	7,397
Noncontrolling Interest, Increase from Subsidiary Equity Issuance	2,400		4,600
RARE Management Team [Member] \| Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Noncontrolling Interest, Decrease from Redemptions or Purchase of Interests	(15,547)
Noncontrolling Interest, Change in Redemption Value	(12,345)
Management Equity Plan [Member] \| Royce [Member]
Noncontrolling Interest [Line Items]
Net Income (Loss) Attributable to Nonredeemable Noncontrolling Interest	8,413	8,403	7,397
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	8,760	8,470	6,401
Stockholders' Equity Attributable to Noncontrolling Interest	29,784	27,731	27,798	22,202
Other Affiliates [Member] \| Noncontrolling Interest [Member]
Noncontrolling Interest [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	1,228	1,509	4,482	$ 1,767
Net Income (Loss) Attributable to Redeemable Noncontrolling Interest	(269)		$ 2,531
Proceeds from (Payments to) Noncontrolling Interests		$ (2,693)
Noncontrolling Interest, Decrease from Distributions to Noncontrolling Interest Holders	(12)
Noncontrolling Interest, Period Increase (Decrease), Foreign Exchange	$ 0