Debt and Credit Facility (Details 2) $ / shares in Units, shares in Millions	3 Months Ended		9 Months Ended
	Dec. 31, 2016 USD ($) $ / shares shares	Jan. 02, 2016 USD ($)	Dec. 31, 2016 USD ($) $ / shares shares	Jan. 02, 2016 USD ($)	Apr. 02, 2016 USD ($)
Short-term Debt [Line Items]
Amortization of Debt Discount (Premium)			$ 9,053,000	$ 9,033,000
Two And Six Two Five Percent Senior Convertible Debentures [Member]
Short-term Debt [Line Items]
Amount of conversion notice received	$ 142,000,000
Debt Instrument, Convertible, Threshold Trading Days	20
Debt Instrument, Convertible, Threshold Percentage of Stock Price Trigger	130.00%
Debt Instrument, Convertible, Threshold Consecutive Trading Days	30 days
Debt Instrument, Convertible, Conversion Ratio	34.6495
Base conversion, block amount of senior convertible debenture	$ 1,000
Convertible debt, conversion price | $ / shares	$ 28.8604		$ 28.8604
Debt Instrument, Face Amount	$ 600,000,000		$ 600,000,000		$ 600,000,000
Debt Instrument, Unamortized Discount	6,477,000		6,477,000		18,135,000
Hedge Accounting Adjustment - Sale Of Interest Rate Swap	1,872,000		1,872,000		5,241,000
Deferred Finance Costs, Own-share Lending Arrangement, Issuance Costs, Net	(603,000)		(603,000)		(1,689,000)
Convertible Debt	594,792,000		594,792,000		585,417,000
Debt Instrument, Convertible, Carrying Amount of Equity Component	66,415,000		$ 66,415,000		$ 66,415,000
Debt Instrument, Convertible, Remaining Discount Amortization Period			5 months 14 days
Debt Instrument, Convertible, If-converted Value in Excess of Principal	1,180,000,000		$ 1,180,000,000
Interest Expense, Debt, Excluding Amortization	3,938,000	$ 3,938,000	11,813,000	11,813,000
Amortization of Financing Costs	362,000	362,000	1,086,000	1,086,000
Amortization of Debt Discount (Premium)	2,763,000	2,763,000	8,289,000	8,289,000
Interest Expense, Debt	$ 7,063,000	$ 7,063,000	$ 21,188,000	$ 21,188,000
Maximum number of common shares to be purchased under call option | shares	20.8		20.8
Price Per Share To Be Purchase By Company Under Call Option | $ / shares			$ 28.86
Warrants, number of shares the holders have the right to purchase | shares	20.8		20.8
Class of Warrant or Right, Exercise Price of Warrants or Rights | $ / shares	$ 40.89		$ 40.89