Accounting Policies - Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended
Jul. 28, 2018	Apr. 27, 2019
Recent Accounting Pronouncements
Lease liability		$ 392,220
Retained Earnings \| ASU 2016-01 - Investments
Recent Accounting Pronouncements
Reclassification of net unrealized gains, before tax	$ 2,100
Reclassification of tax expense	500
Accumulated Other Comprehensive Income (Loss) \| ASU 2016-01 - Investments
Recent Accounting Pronouncements
Reclassification of net unrealized gains, before tax	(2,100)
Reclassification of tax expense	$ (500)
Restatement Adjustment \| Minimum \| ASU 2016-02
Recent Accounting Pronouncements
Right of use asset		300,000
Lease liability		0
Restatement Adjustment \| Maximum \| ASU 2016-02
Recent Accounting Pronouncements
Right of use asset		(325,000)
Lease liability		$ 0

Amount of the cumulative effect on retained earnings before related income tax effect.

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Amount of lessee's right to use underlying asset under operating lease.

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