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Employee Benefits - Pension Plans Narrative (Details) £ in Millions, $ in Millions | 1 Months Ended | 3 Months Ended | 12 Months Ended
--- | --- | --- | ---
Mar. 31, 2016 USD ($) | Dec. 31, 2016 USD ($) | Jun. 30, 2016 GBP (£) | Jun. 30, 2016 USD ($) | Dec. 31, 2016 USD ($) | Dec. 31, 2015 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Percentage of the Company's projected benefit obligation |  | 92.00% |  |  | 92.00% |
U.S. Pension Plan |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Plans with PBO in excess of the fair value of plan assets, PBO |  | $ 2,900 |  |  | $ 2,900 | $ 3,200
Plans with ABO in excess of the fair value of plan assets, ABO |  | 2,900 |  |  | 2,900 | 3,200
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets |  | 1,700 |  |  | 1,700 | 2,000
Defined benefit plan, benefits paid |  | 281 |  |  | 139 | 133
Defined benefit plan, benefit obligation, period increase (decrease) |  | 325 |  |  |  |
Defined benefit plan, settlements, benefit obligation |  | 158 |  |  | 281 | 0
Future amortization of loss |  |  |  |  | 52 |
U.K. |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Plans with PBO in excess of the fair value of plan assets, PBO |  | 1,200 |  |  | 1,200 | 1,200
Plans with ABO in excess of the fair value of plan assets, ABO |  | 1,200 |  |  | 1,200 | 1,200
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets |  | 1,100 |  |  | 1,100 | 1,100
Plans with PBO in excess of the fair value of plan assets |  | 1,100 |  |  | 1,100 | 1,100
Defined benefit plan, benefits paid |  |  | £ 116 | $ 159 | 242 | 217
Defined benefit plan, benefit obligation, period increase (decrease) |  |  | 103 | 141 |  |
Defined benefit plan, settlements, benefit obligation |  |  | £ 42 | $ 61 | 159 | 0
Future amortization of loss |  |  |  |  | 41 |
Effect of UK Plan insurance contract | $ 267 |  |  |  |  |
Other |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |
Plans with PBO in excess of the fair value of plan assets, PBO |  | 1,200 |  |  | 1,200 | 1,200
Plans with ABO in excess of the fair value of plan assets, ABO |  | 1,100 |  |  | 1,100 | 1,100
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets |  | 1,000 |  |  | 1,000 | 1,000
Plans with PBO in excess of the fair value of plan assets |  | $ 1,000 |  |  | 1,000 | 1,000
Defined benefit plan, benefits paid |  |  |  |  | 39 | 38
Defined benefit plan, settlements, benefit obligation |  |  |  |  | $ 0 | $ 0

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- Definition Represents the percentage of the company's total pension obligations represented within the tables provided. + References No definition available. + Details
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- Definition Amount recognized in net periodic benefit cost and other comprehensive income. + References No definition available. + Details
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- Definition Net increase or decrease in the plan benefit obligation during the reporting period. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition The amount of payments made for which participants are entitled under a pension plan, including pension benefits, death benefits, and benefits due on termination of employment. Also includes payments made under a postretirement benefit plan, including prescription drug benefits, health care benefits, life insurance benefits, and legal, educational and advisory services. This item represents a periodic decrease to the plan obligations and a decrease to plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 60 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=6414203&loc=d3e39716-114964 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Benefits -URI http://asc.fasb.org/extlink&oid=49170737 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(6) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Postretirement Benefits -URI http://asc.fasb.org/extlink&oid=6521376 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(5) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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- Definition Amount included in accumulated other comprehensive income (AOCI) related to gain (loss) expected to be recognized as components of net periodic benefit cost for the fiscal year that follows the most recent annual statement of financial position. + References No definition available. + Details
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- Definition If aggregate disclosures are presented, the aggregate pension accumulated benefit obligation for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=73719040&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 + Details
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- Definition If aggregate disclosures are presented, the aggregate fair value of plan assets for pension plans with accumulated benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=73719040&loc=d3e4179-114921 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 + Details
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- Definition If aggregate disclosures are presented, the aggregate benefit obligation for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 + Details
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- Definition If aggregate disclosures are presented, the aggregate fair value of plan assets for plans with benefit obligations in excess of plan assets as of the measurement date of each statement of financial position presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e2417-114920 + Details
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- Definition The amount of decrease that relates to an irrevocable action that relieves the employer (or the plan) of primary responsibility for a benefit obligation and eliminates significant risks related to the obligation and the assets used to effect the settlement. Examples of transactions that constitute a settlement include (a) making lump-sum cash payments to plan participants in exchange for their rights to receive specified benefits and (b) purchasing nonparticipating annuity contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Section 15 -Paragraph 6 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=7577095&loc=d3e8001-114927 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(10) -URI http://asc.fasb.org/extlink&oid=65897934&loc=d3e1928-114920 + Details
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