Goodwill and Intangible Assets - Changes in the Carrying Amount of Goodwill (Details) - USD ($) $ in Thousands	12 Months Ended
Jan. 26, 2019	Jan. 27, 2018
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill gross	$ 521,516	$ 517,510
Accumulated impairment losses	(195,767)	$ (195,767)
Beginning balance	321,743
Goodwill from fiscal 2019 acquisition	4,097
Purchase price allocation adjustments from fiscal 2019 acquisition	(91)
Ending balance	$ 325,749

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount before accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

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Amount of accumulated impairment loss for an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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Amount of increase (decrease) from adjustments after acquisition date under purchase accounting of an asset representing the future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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