Short-Term Borrowings and Long-Term Debt Interest Rate Swap - Revolving Credit Facility (Details) - USD ($) $ in Thousands	3 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 23, 2014
Line of Credit Facility [Line Items]
Derivative, Term of Contract	4 years 245 days
Revolving Credit Facility [Member] | Interest Rate Swap [Member]
Line of Credit Facility [Line Items]
Derivative, Fixed Interest Rate	2.30%
Derivative, Notional Amount	$ 500,000
Accumulated Other Comprehensive Income (Loss), Cumulative Changes in Net Gain (Loss) from Cash Flow Hedges, Effect Net of Tax	(2,683)
Deferred Tax Assets, Hedging Transactions	1,686
Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member]
Line of Credit Facility [Line Items]
Derivative Liability, Not Subject to Master Netting Arrangement	(6,522)
Derivative, Loss on Derivative	(12,757)	$ (5,398)
Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member] | Interest Rate Swap [Member]
Line of Credit Facility [Line Items]
Derivative, Notional Amount			$ 250,000
Designated as Hedging Instrument [Member] | Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member] | Interest Rate Swap [Member]
Line of Credit Facility [Line Items]
Derivative Liability, Not Subject to Master Netting Arrangement	(4,369)
Interest Expense [Member] | Cash Flow Hedging [Member] | Consolidated Entity Excluding Consolidated Investment Vehicles Before Eliminations [Member] | Interest Rate Swap [Member]
Line of Credit Facility [Line Items]
Derivative, Loss on Derivative	$ (527)	$ 0