Stockholders' Equity and Noncontrolling Interests - Reclassifications from AOCI (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Dec. 31, 2017	Jan. 01, 2017	Dec. 31, 2017	Jan. 01, 2017
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gain on cash flow hedging derivative instruments	$ (491,970)	$ (408,315)	$ (1,408,913)	$ (1,254,678)
Derivatives in cash flow hedging relationships
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Tax expense (benefit)	168	528	(199)	915
Net of tax	(287)	(903)	338	(1,566)
Derivatives in cash flow hedging relationships | Reclassification out of Accumulated Other Comprehensive Income
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Net gain on cash flow hedging derivative instruments	(455)	(1,431)	(537)	(2,481)
Defined benefit pension costs
Reclassification Adjustment out of Accumulated Other Comprehensive Income [Line Items]
Prior service costs and deferrals	434	314	1,304	1,096
Tax expense (benefit)	(103)	(116)	(308)	(349)
Net of tax	$ 331	$ 198	$ 996	$ 747