Stock-Based Compensation (Narrative) (Details)
$ / shares in Units, $ in Millions

6 Months Ended

Jul. 01, 2017

USD ($)

$ / shares

shares

Restricted Stock Units RSU [Member] | Stock Incentive Plan [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares

653,982

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value

$ 9.31

Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Share Based Awards Other Than Options | $

$ 6.1

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period

2 years 8 months 12 days

Common Share Entitlement Per Vested Unit | shares

1

Restricted Stock Units RSU [Member] | CEO Plan [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares

100,000

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value

$ 7

Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Share Based Awards Other Than Options | $

$ 0.7

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period

3 years

Disclosure Of Share Based Compensation Arrangements By Share Based Payment Award TextBlock

Mr. Colo was granted 100,000 RSUs, of which 50,000 of the RSUs granted were contingent on Mr. Colo purchasing an aggregate value of $1.0 million of Common Shares in the open market.

Special Performance Units [Member] | CEO Plan [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares

277,780

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value

$ 2.79

Share-based Compensation Arrangement by Share-based Payment Award, Method of Measuring Cost of Award

Monte Carlo

Common Share Entitlement Per Vested Unit | shares

1

Special Performance Units [Member] | CEO Plan [Member] | First One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

$ 11

Special Performance Units [Member] | CEO Plan [Member] | Second One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

14

Special Performance Units [Member] | CEO Plan [Member] | Third One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

$ 18

Special Stock Options [Member] | CEO Plan [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares

473,940

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value

$ 1.84

Share-based Compensation Arrangement by Share-based Payment Award, Method of Measuring Cost of Award

Monte Carlo

Special Stock Options [Member] | CEO Plan [Member] | First One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

$ 11

Special Stock Options [Member] | CEO Plan [Member] | Second One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

14

Special Stock Options [Member] | CEO Plan [Member] | Third One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

$ 18

Performance Shares [Member] | Stock Incentive Plan [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares

1,386,335

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value

$ 5.9

Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Share Based Awards Other Than Options | $

$ 8.2

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period

3 years

Performance Shares [Member] | Stock Incentive Plan [Member] | First One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

$ 11

Performance Shares [Member] | Stock Incentive Plan [Member] | Second One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

14

Performance Shares [Member] | Stock Incentive Plan [Member] | Third One-Third of Options [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Stock Price for Vesting

$ 18

Options [Member] | Stock Incentive Plan [Member]

Share-based Compensation, Shares Authorized under Stock Option Plans, Exercise Price Range [Line Items]

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Gross | shares

823,236

Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period, Weighted Average Grant Date Fair Value

$ 4.24

Share-based Compensation Arrangement by Share-based Payment Award, Award Vesting Period

3 years

Employee Service Share Based Compensation Nonvested Awards Total Compensation Cost Not Yet Recognized Stock Options | $

$ 3.5