Share-Based Compensation - Schedule of Total Return (Details) - OPP	Jun. 02, 2015
Performance Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute component, base percent	4.00%
Relative component, base percent	4.00%
Absolute component of total return, percent	21.00%
Relative component, 100% of cumulative total return, percent	18.00%
Relative component, 50% of cumulative total return, percent	0.00%
Relative component, 0% of cumulative total return, percent	0.00%
Performance Period \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Relative component, 50%-100% of cumulative total return, percent	0.00%
Performance Period \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Relative component, 50%-100% of cumulative total return, percent	18.00%
Annual Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute component, base percent	4.00%
Relative component, base percent	4.00%
Absolute component of total return, percent	7.00%
Relative component, 100% of cumulative total return, percent	6.00%
Relative component, 50% of cumulative total return, percent	0.00%
Relative component, 0% of cumulative total return, percent	0.00%
Annual Period \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Relative component, 50%-100% of cumulative total return, percent	0.00%
Annual Period \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Relative component, 50%-100% of cumulative total return, percent	6.00%
Interim Period
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Absolute component, base percent	4.00%
Relative component, base percent	4.00%
Absolute component of total return, percent	14.00%
Relative component, 100% of cumulative total return, percent	12.00%
Relative component, 50% of cumulative total return, percent	0.00%
Relative component, 0% of cumulative total return, percent	0.00%
Interim Period \| Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Relative component, 50%-100% of cumulative total return, percent	0.00%
Interim Period \| Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Relative component, 50%-100% of cumulative total return, percent	12.00%

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Share Based Compensation Arrangement By Share Based Payment Award, Absolute Component of Total Return, Percent

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Share Based Compensation Arrangement By Share Based Payment Award, Relative Component, 100% of Cumulative Total Return, Percent

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