Income Taxes - Reconciliation of Income Taxes (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 28, 2019	Dec. 29, 2018	Dec. 30, 2017
Effective Income Tax Rate Reconciliation, Amount [Abstract]
Income tax expense (benefit) based on Canadian statutory rates	$ 2.5	$ 6.4	$ (8.7)
Foreign tax rate differential	(11.1)	(2.6)	(1.3)
Local taxes	2.1	0.5	(0.2)
Nontaxable interest income	(8.4)	(9.8)	(11.3)
Impact of intercompany transactions and dividends	12.2	1.0	(9.2)
Nontaxable capital gains	0.0	0.0	(3.7)
Income tax credits	(0.5)	0.0	0.0
Change in enacted tax rates	(0.1)	3.4	(32.7)
Change in valuation allowance	19.7	(4.2)	45.8
Change in uncertain tax positions	0.3	(3.4)	(2.4)
Equity compensation	1.5	1.5	1.1
Permanent differences	1.6	1.1	(0.6)
Outside basis differences on discontinued operations	0.0	0.0	(3.8)
Adjustments to deferred taxes	(10.4)	0.7	(3.4)
Other items	0.1	0.6	0.4
Income tax expense (benefit)	$ 9.5	$ (4.8)	$ (30.0)

Deferred income tax adjustment before tax.

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Income tax reconciliation effect of discontinued operations.

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Income tax reconciliation intercompany transactions and nontaxable dividend income.

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Income Tax Reconciliation Non Tax Portion Of Capital Gain Loss

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Income Tax Reconciliation Tax Exempt Interest Income

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to increase (decrease) in the valuation allowance for deferred tax assets.

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Amount of reported income tax expense (benefit) in excess of (less than) expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to nondeductible expense for award under share-based payment arrangement. Includes, but is not limited to, expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to revisions of previously reported income tax expense (benefit).

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Amount of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to tax credits. Including, but not limited to, research credit, foreign tax credit, investment tax credit, and other tax credits.

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