Investments and Fair Value Measurements-Fin Assets and Liabilities 1 (Details 2) - USD ($)	Jan. 03, 2016	Dec. 28, 2014
Financial Liabilities measured at fair value on a recurring basis
Derivative liabilities	$ 1,747,000	$ 8,224,000
Significant Unobservable Inputs (Level 3) [Member]
Financial assets measured at fair value on a recurring basis
Total financial assets	0	0
Financial Liabilities measured at fair value on a recurring basis
Total financial liabilities	0	0
Fair Value, Measurements, Recurring [Member]
Financial assets measured at fair value on a recurring basis
Total financial assets	3,916,012,000	4,776,694,000
Financial Liabilities measured at fair value on a recurring basis
Total financial liabilities	1,747,000	8,224,000
Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets measured at fair value on a recurring basis
Total financial assets	1,303,513,000	558,295,000
Financial Liabilities measured at fair value on a recurring basis
Total financial liabilities	0	0
Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets measured at fair value on a recurring basis
Total financial assets	2,612,499,000	4,218,399,000
Financial Liabilities measured at fair value on a recurring basis
Total financial liabilities	1,747,000	8,224,000
Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial assets measured at fair value on a recurring basis
Total financial assets	0	0
Financial Liabilities measured at fair value on a recurring basis
Total financial liabilities	0	0
Derivative Liabilities [Member] | Fair Value, Measurements, Recurring [Member]
Financial Liabilities measured at fair value on a recurring basis
Derivative liabilities	1,747,000	8,224,000
Derivative Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial Liabilities measured at fair value on a recurring basis
Derivative liabilities	0	0
Derivative Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial Liabilities measured at fair value on a recurring basis
Derivative liabilities	1,747,000	8,224,000
Derivative Liabilities [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial Liabilities measured at fair value on a recurring basis
Derivative liabilities	0	0
Money Market Funds [Member] | Fair Value, Measurements, Recurring [Member]
Financial assets measured at fair value on a recurring basis
Money market funds	1,180,614,000	533,133,000
Money Market Funds [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets measured at fair value on a recurring basis
Money market funds	1,180,614,000	533,133,000
Money Market Funds [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets measured at fair value on a recurring basis
Money market funds	0	0
Money Market Funds [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial assets measured at fair value on a recurring basis
Money market funds	0	0
Fixed Income Securities [Member] | Fair Value, Measurements, Recurring [Member]
Financial assets measured at fair value on a recurring basis
Fixed income securities	2,732,022,000	4,238,761,000
Fixed Income Securities [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets measured at fair value on a recurring basis
Fixed income securities	122,899,000	25,162,000
Fixed Income Securities [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets measured at fair value on a recurring basis
Fixed income securities	2,609,123,000	4,213,599,000
Fixed Income Securities [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial assets measured at fair value on a recurring basis
Fixed income securities	0	0
Derivative Assets [Member] | Fair Value, Measurements, Recurring [Member]
Financial assets measured at fair value on a recurring basis
Derivative assets	3,376,000	4,800,000
Derivative Assets [Member] | Fair Value, Measurements, Recurring [Member] | Quoted Prices in Active Markets for Identical Assets (Level 1) [Member]
Financial assets measured at fair value on a recurring basis
Derivative assets	0	0
Derivative Assets [Member] | Fair Value, Measurements, Recurring [Member] | Significant Other Observable Inputs (Level 2) [Member]
Financial assets measured at fair value on a recurring basis
Derivative assets	3,376,000	4,800,000
Derivative Assets [Member] | Fair Value, Measurements, Recurring [Member] | Significant Unobservable Inputs (Level 3) [Member]
Financial assets measured at fair value on a recurring basis
Derivative assets	$ 0	$ 0