The total fair value of shares issued during the period under a deferred compensation arrangement.

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Commitments and Contingencies Commitments Related to Noncontrolling Interests (Details) - USD ($) $ in Thousands	12 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
Other Commitments [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	$ 692,376	$ 732,295	$ 677,772	$ 175,785
Noncontrolling Interest [Member]
Other Commitments [Line Items]
Redeemable Noncontrolling Interest, Equity, Carrying Amount	540,595	$ 573,950	$ 591,254	$ 68,922
Management Equity Plan [Member]
Other Commitments [Line Items]
Deferred Compensation Arrangement with Individual, Fair Value of Shares Issued	81,794
TRG [Member]
Other Commitments [Line Items]
Payments to Noncontrolling Interests	15,547
Payments of Ordinary Dividends, Noncontrolling Interest	$ 981