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Employee Benefit Plans (Asset Class) (Details) | 12 Months Ended
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Dec. 31, 2016
Pension Plan [Member] | Short-term securities |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 0.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 5.00%
Pension Plan [Member] | Fixed Income Funds [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 35.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 50.00%
Pension Plan [Member] | Equity Securities, Canadian [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 12.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 22.00%
Pension Plan [Member] | Equity Securities, Non Canadian [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 36.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 50.00%
Non-pension Benefit Plans [Member | Short-term securities |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 0.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 2.00%
Non-pension Benefit Plans [Member | Fixed Income Funds [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 40.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 48.00%
Non-pension Benefit Plans [Member | Equity Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 50.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 61.00%
United States Postretirement Benefit Plan of US Entity [Member] | Short-term securities |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 10.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 50.00%
United States Postretirement Benefit Plan of US Entity [Member] | Fixed Income Funds [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 0.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 40.00%
United States Postretirement Benefit Plan of US Entity [Member] | Equity Securities, United States [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 30.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 60.00%
United States Postretirement Benefit Plan of US Entity [Member] | Equity Securities, Non United States [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined Benefit Plan, Target Plan Asset Allocations Range Minimum | 0.00%
Defined Benefit Plan, Target Plan Asset Allocations Range Maximum | 60.00%

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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
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- Definition Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (c)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2446-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(i) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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