Income Taxes - Uncertainty in Income Taxes - Narrative (Detail) - USD ($)
$ in Millions |
3 Months Ended |
9 Months Ended |
|
|
Jan. 29, 2017 |
Jan. 29, 2017 |
May 01, 2016 |
Jan. 31, 2016 |
| Income Taxes [Line Items] |
|
|
|
|
| Unrecognized tax benefits |
$ 13.4
|
$ 13.4
|
$ 14.9
|
$ 13.2
|
| Unrecognized tax benefits that would favorably impact effective income tax rate if recognized |
1.8
|
1.8
|
3.8
|
3.5
|
| Unrecognized tax benefits for which significant change is reasonably possible |
13.4
|
13.4
|
|
|
| Income tax benefit recognized from reversal of uncertain income tax position |
2.1
|
$ 2.1
|
|
|
| Canadian Federal Returns [Member] | Minimum [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Income tax returns, years subject to examination |
|
2010
|
|
|
| Canadian Provincial (Quebec) Returns [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Statute of limitations for 2009 income tax, expiration month and year |
|
2017-04
|
|
|
| Canadian Provincial (Quebec) Returns [Member] | Minimum [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Income tax returns, years subject to examination |
|
2009
|
|
|
| Income tax examination, year under examination |
|
2013
|
|
|
| Canadian Provincial (Quebec) Returns [Member] | Maximum [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Income tax examination, year under examination |
|
2015
|
|
|
| China Income Tax Returns [Member] | Minimum [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Income tax returns, years subject to examination |
|
2011
|
|
|
| Internal Revenue Service (IRS) [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Income tax examination, year under examination |
|
2014
|
|
|
| United States Federal and State Income Tax [Member] | Minimum [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Income tax returns, years subject to examination |
|
2005
|
|
|
| Non-current Deferred Income Taxes [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Unrecognized tax benefits |
11.6
|
$ 11.6
|
11.1
|
9.7
|
| Income Taxes Payable - Long-Term [Member] |
|
|
|
|
| Income Taxes [Line Items] |
|
|
|
|
| Unrecognized tax benefits |
$ 1.8
|
$ 1.8
|
$ 3.8
|
$ 3.5
|