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Shareholders' Equity - Additional Information (Detail) € / shares in Units, $ / shares in Units, $ in Millions |  | 1 Months Ended | 3 Months Ended | 12 Months Ended |  |  |  |  |  |  |
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May. 27, 2015 $ / shares | Dec. 31, 2014 USD ($) shares | Mar. 31, 2016 $ / shares | Dec. 31, 2015 USD ($) $ / shares shares | Sep. 30, 2015 USD ($) $ / shares | Jun. 30, 2015 USD ($) $ / shares | Mar. 31, 2015 USD ($) $ / shares | Dec. 31, 2014 USD ($) $ / shares shares | Sep. 30, 2014 USD ($) $ / shares | Jun. 30, 2014 USD ($) $ / shares | Dec. 31, 2013 USD ($) $ / shares | Sep. 30, 2013 USD ($) $ / shares | Jun. 30, 2013 USD ($) $ / shares | Dec. 31, 2015 USD ($) $ / shares shares | Dec. 31, 2014 USD ($) $ / shares shares | Dec. 31, 2013 USD ($) $ / shares | Dec. 31, 2012 $ / shares | Dec. 31, 2008 USD ($) shares | Dec. 31, 2007 | Dec. 31, 2002 shares | Dec. 31, 2001 shares | Dec. 31, 2015 EUR (€) € / shares shares | Dec. 31, 2014 € / shares | Jun. 13, 2014 shares | May. 20, 2012 | May. 20, 2011 | May. 20, 2010 | Jan. 22, 2007 shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Total Authorized share capital | € |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | € 1,810,000,000 |  |  |  |  |  |
Common stock, shares authorized |  | 1,200,000,000 |  | 1,200,000,000 |  |  |  | 1,200,000,000 |  |  |  |  |  | 1,200,000,000 | 1,200,000,000 |  |  |  |  |  |  | 1,200,000,000 |  |  |  |  |  |
Preference stock, shares authorized |  | 540,000,000 |  | 540,000,000 |  |  |  | 540,000,000 |  |  |  |  |  | 540,000,000 | 540,000,000 |  |  |  |  |  |  | 540,000,000 |  |  |  |  |  | 540,000,000
Common stock, nominal value | € / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | € 1.04 | € 1.04 |  |  |  |  |
Common stock, shares issued |  | 910,797,305 |  | 910,967,920 |  |  |  | 910,797,305 |  |  |  |  |  | 910,967,920 | 910,797,305 |  |  |  |  |  |  | 910,967,920 |  |  |  |  |  |
Common stock, shares outstanding |  | 873,939,583 |  | 878,537,339 |  |  |  | 873,939,583 |  |  |  |  |  | 878,537,339 | 873,939,583 |  |  |  |  |  |  | 878,537,339 |  |  |  |  |  |
Shares issued as a percentage of par value of the preference shares to be issued |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 25.00%
Preference shares outstanding maximum period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 2 years |  |  |  |  |  |  |  |  |
Preference share issued |  | 0 |  | 0 |  |  |  | 0 |  |  |  |  |  | 0 | 0 |  |  |  |  |  |  | 0 |  |  |  |  |  |
Repurchase of common shares authorized to repurchase | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 30 |  |  |  |  |  |  |  |  |  |
Acquisition of shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 29,520,220 |  |  |  |  |  |  |  |  |  |
Number of common shares authorized to repurchase |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 20,000,000 |  |  |  |
Company owned treasury shares |  |  |  | 32,430,581 |  |  |  |  |  |  |  |  |  | 32,430,581 |  |  |  |  |  |  |  | 32,430,581 |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration programs |  |  |  | 30,489,639 |  |  |  |  |  |  |  |  |  | 30,489,639 |  |  |  |  |  |  |  | 30,489,639 |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration during the year |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,427,141 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expiration period of options after date of grant,in years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |  |
Vesting period of awards |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 30 days |  |  |  |  |  |  |  |
Weighted average remaining contractual life options |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 1 month 6 days | 3 months 18 days |  |  |  |  |  |  |  |  |  |  |  |
Total intrinsic value of options exercised | $ |  |  |  | $ 1 |  |  |  |  |  |  |  |  |  | $ 1 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Compensation cost, excluding payroll tax and social contribution, capitalized as part of inventory | $ |  | $ 2 |  | 2 |  |  |  | $ 2 |  |  | $ 2 |  |  | 2 | $ 2 | $ 2 |  |  |  |  |  |  |  |  |  |  |  |
Total unrecognized compensation cost related to the grant of unvested shares | $ |  |  |  | $ 39 |  |  |  |  |  |  |  |  |  | $ 39 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee service share-based compensation, unvested awards, total compensation cost not yet recognized, period for recognition |  |  |  |  |  |  |  |  |  |  |  |  |  | 9 months |  |  |  |  |  |  |  |  |  |  |  |  |  |
Deferred income tax benefit relating to unvested share based compensation expense | $ |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 2 | 1 | $ 5 |  |  |  |  |  |  |  |  |  |  |  |
Dividends, per share | $ / shares | $ 0.40 |  |  | $ 0.10 | $ 0.10 | $ 0.10 | $ 0.10 | $ 0.10 | $ 0.10 | $ 0.10 | $ 0.10 | $ 0.10 | $ 0.10 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend paid | $ |  | 87 |  | $ 88 | $ 78 | $ 88 | $ 88 | $ 4 | $ 85 | $ 89 | $ 89 | $ 93 | $ 75 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends payable to stockholders | $ |  | $ 87 |  | $ 97 | $ 9 |  |  | $ 87 |  |  |  |  |  | $ 97 | $ 87 |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend payable date |  | 2014-12 |  | 2015-12 |  |  | 2015-03 | 2014-12 | 2014-09 | 2014-06 | 2013-12 |  |  | 2015-12 | 2014-12 | 2013-12 |  |  |  |  |  | 2015-12 |  |  |  |  |  |
Scenario, Forecast [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends, per share | $ / shares |  |  | $ 0.10 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividend payable date |  |  | 2016-03 |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
March 2014 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Dividends, per share | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 0.10 |  |  |  |  |  |  |  |  |  |  |  |
Dividend paid | $ |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 89 |  |  |  |  |  |  |  |  |  |  |  |
Dividend payable date |  |  |  |  |  |  |  |  |  |  | 2014-03 |  |  |  |  | 2014-03 |  |  |  |  |  |  |  |  |  |  |  |
Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration during the year |  |  |  |  |  |  |  |  |  |  |  |  |  | 4,427,141 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Awards granted, Number of shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 7,017,886 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting period of awards |  |  |  |  |  |  |  |  |  |  |  |  |  | 3 years |  |  |  |  |  |  |  |  |  |  |  |  |  |
Vesting schedule for Supervisory Board |  |  |  |  |  |  |  |  |  |  |  |  |  | One third of the total number of awards granted |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Stock Option Plan, 2001 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Awards granted, Number of shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 60,000,000 |  |  |  |  |  |  |
Stock option grant installment period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 5 years |  |  |  |  |  |  |
Expiration period of options after date of grant,in years |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 10 years |  |  |  |  |  |  |
Supervisory Board Option Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 12,000 |  |  |  |  |  |  |  |
Advisor To Supervisory Board [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award, Options, Grants in Period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,000 |  |  |  |  |  |  |  |
Supervisory Board 2012 Plan [Member] | Supervisory Board [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Awards are granted at the nominal value of the share | € / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | € 1.04 |  |  |  |  |  |
2013 CEO Special Bonus [Member] | Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration during the year |  |  |  |  |  |  |  |  |  |  |  |  |  | 21,282 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Awards granted, Number of shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 21,283 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average grant-date fair value of nonvested shares granted to employees under Employee Plan | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9.35 |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2012 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average grant-date fair value of nonvested shares granted to employees under Employee Plan | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 4.87 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares to vest |  |  |  |  |  |  |  |  |  |  |  |  |  | Two thirds of the awards granted will fully vest |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2012 [Member] | Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration during the year |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,371,370 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2013 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average grant-date fair value of nonvested shares granted to employees under Employee Plan | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9.55 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares to vest |  |  |  |  |  |  |  |  |  |  |  |  |  | One third of the awards granted will fully vest |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2013 [Member] | Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration during the year |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,370,601 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2014 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average grant-date fair value of nonvested shares granted to employees under Employee Plan | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9.23 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2014 [Member] | Performance Conditions [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares to vest |  |  |  |  |  |  |  |  |  |  |  |  |  | One third of the awards granted will fully vest |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2014 [Member] | Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration during the year |  |  |  |  |  |  |  |  |  |  |  |  |  | 1,618,774 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2015 [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average grant-date fair value of nonvested shares granted to employees under Employee Plan | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 7.62 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Number of shares to vest |  |  |  |  |  |  |  |  |  |  |  |  |  | One third of the awards subject to performance conditions are expected to vest |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2015 [Member] | Performance Conditions [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Awards granted, Number of shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 2,993,150 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2015 [Member] | Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Awards granted, Number of shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 6,962,120 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Employee Plan 2009 [Member] | Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sub plan for employees of Company's European subsidiaries for statutory payroll tax purposes nonvested shares vested over requisite service period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 36.00% | 32.00% | 32.00% |
Employee Plan 2009 [Member] | Employees [Member] | France [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Sub plan for employees of Company's European subsidiaries for statutory payroll tax purposes nonvested shares vested over requisite service period |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | 36.00% | 64.00% |  |
2012 CEO Special Bonus [Member] | Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration during the year |  |  |  |  |  |  |  |  |  |  |  |  |  | 33,620 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average grant-date fair value of nonvested shares granted to employees under Employee Plan | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 6.32 |  |  |  |  |  |  |  |  |  |  |
2014 CEO Special Bonus [Member] | Employees [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |
Transfer of treasury shares to employees under the Company's share based remuneration during the year |  |  |  |  |  |  |  |  |  |  |  |  |  | 11,494 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Awards granted, Number of shares |  |  |  |  |  |  |  |  |  |  |  |  |  | 34,483 |  |  |  |  |  |  |  |  |  |  |  |  |  |
Weighted average grant-date fair value of nonvested shares granted to employees under Employee Plan | $ / shares |  |  |  |  |  |  |  |  |  |  |  |  |  |  | $ 9.35 |  |  |  |  |  |  |  |  |  |  |  |  |

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