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Pension and Other Postretirement Benefits - Additional Information (Detail) (USD $) In Millions, unless otherwise specified | 12 Months Ended
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Dec. 31, 2013 Y | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2013 Maximum [Member] | Dec. 31, 2013 Minimum [Member] | Dec. 31, 2013 Canada [Member] | Dec. 31, 2014 Subsequent Event [Member] | Dec. 31, 2013 Pension Benefits [Member] Y | Dec. 31, 2013 Foreign Pension Plan, Defined Benefit [Member] Y | Dec. 31, 2013 10-Year Moving Average [Member] Y | Dec. 31, 2013 20-Year Moving Average [Member] Y
Defined Benefit Plan Disclosure [Line Items] |  |  |  |  |  |  |  |  |  |  |
Average duration refined yield curve model parallels the plans, years | 10 |  |  |  |  |  |  |  |  |  |
Percentage increase in rate of compensation |  |  |  |  |  |  |  | 3.50% |  |  |
Average period over which rate of compensation increases, years |  |  |  |  |  |  |  | 5 |  |  |
Average period of historical returns used to calculate expected future returns, in years | 5 |  |  |  |  |  |  |  | 4 |  |
Period of moving averages used for historical data points used to determine the expected long-term rate of return on plan assets, in years |  |  |  |  |  |  |  |  |  | 10 | 20
Expected long term rate of return on plan assets | 8.50% | 8.50% | 8.50% |  |  |  | 8.00% |  |  |  |
Decrease in expected long-term rate of return | 0.50% |  |  |  |  |  |  |  |  |  |
Health care cost trend rate assumed for next year | 5.50% | 6.00% | 6.50% |  |  |  |  |  |  |  |
Health care cost trend rate | 4.50% | 4.50% | 5.00% | 3.50% | (7.50%) |  |  |  |  |  |
Number of years over actual annual health care cost trend experience | 3 |  |  |  |  |  |  |  |  |  |
Collateral, which exceeds the value of the securities loaned |  |  |  | 105.00% | 102.00% |  |  |  |  |  |
Cash contribution to pension plans | $ 462 | $ 561 | $ 336 |  |  |  |  |  |  |  |
Minimum required cash contribution to pension plan in 2014 | 625 |  |  |  |  | 90 |  |  | 435 |  |
Expenses related to saving and investment plans | $ 149 | $ 146 | $ 139 |  |  |  |  |  |  |  |

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- Definition Period of moving averages used for historical data points used to determine the expected long-term rate of return on plan assets. + References No definition available. + Details
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- Definition An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 30 -Glossary Expected Long-Term Rate of Return on Plan Assets -URI http://asc.fasb.org/extlink&oid=6512013 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (k)(3) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition Expected rate of compensation increases (for pay-related plans). + 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 (k)(2) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 + Details
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- Definition The assumed health care cost trend rate for the next year used to measure the expected cost of benefits covered by the plan (gross eligible charges). This is based upon the annual rate of change in the cost of health care benefits currently provided by the postretirement benefit plan, due to factors other than changes in the composition of the plan population by age and dependency status. + 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 (l) -URI http://asc.fasb.org/extlink&oid=28361610&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Health Care Cost Trend Rate -URI http://asc.fasb.org/extlink&oid=6514820 + Details
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- Definition The amount of the cost recognized during the period for defined contribution plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 70 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=6414718&loc=d3e28014-114942 + Details
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