Income Taxes (Schedule of Deferred Tax Assets and Deferred Tax Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 28, 2019
Deferred tax assets:
Accrued expenses	$ 63,080	$ 31,995
Tax credits and separate return net operating losses	17,976	19,186
Deferred Tax Asset, Contract and service revenues and costs	9,383	0
Share based compensation	49,650	52,643
Deferred Tax Assets, Lease Liability	23,928	29,939
Other	17,554	12,701
Gross deferred tax assets	181,571	146,464
Valuation Allowance	(3,384)	0
Total deferred tax assets	178,187	146,464
Deferred tax liabilities:
Software development costs	(270,041)	(247,217)
Depreciation and amortization	(204,568)	(171,267)
Prepaid expenses	(37,547)	(39,311)
Contract and service revenues and costs	0	(12,112)
Deferred Tax Liability, Lease Right-of-use Asset	(20,639)	(28,100)
Other	(9,260)	(10,549)
Total deferred tax liabilities	(542,055)	(508,556)
Net deferred tax liability	$ (363,868)	$ (362,092)