Summary of Impact of Adoption of New Accounting Pronouncements on Balance Sheets (Detail) - USD ($) $ in Thousands	Jan. 26, 2019	Apr. 28, 2018	Jan. 27, 2018
Assets
Prepaid expenses and other current assets	$ 68,178	$ 65,153	$ 79,175
Liabilities and Shareholders' Equity
Accrued liabilities	271,623	260,209	285,598
Gift card liabilities	239,296	323,465	358,609
Deferred taxes	72,147	52,044	58,118
Retained earnings	(156,965)	(216,236)	$ (183,064)
Calculated under Revenue Guidance in Effect before Topic 606 \| ASU 2014-09
Assets
Prepaid expenses and other current assets	68,449
Liabilities and Shareholders' Equity
Accrued liabilities	270,516
Gift card liabilities	319,739	323,465
Deferred taxes	52,044
Retained earnings	(218,684)
Difference between Revenue Guidance in Effect before and after Topic 606 \| ASU 2014-09
Assets
Prepaid expenses and other current assets	(271)
Liabilities and Shareholders' Equity
Accrued liabilities	1,107
Gift card liabilities	(80,443)	$ (90,147)
Deferred taxes	20,103
Retained earnings	$ 61,719

Carrying value as of the balance sheet date of obligations incurred and payable, pertaining to costs that are statutory in nature, are incurred on contractual obligations, or accumulate over time and for which invoices have not yet been received or will not be rendered. Examples include taxes, interest, rent and utilities. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Carrying value as of the balance sheet date of the liability for outstanding gift cards. Retail customers purchase gift cards or gift certificates that can be redeemed at a later date for merchandise or services; those unredeemed represent a liability of the entity because the revenue is being deferred.

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Amount of asset related to consideration paid in advance for costs that provide economic benefits in future periods, and amount of other assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer.

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