Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to impairment loss.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SAB TOPIC 6.I)
-URI http://asc.fasb.org/extlink&oid=34349781&loc=d3e330036-122817

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 12
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32687-109319

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-SubTopic 10
-Section 50
-Paragraph 13
-URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32698-109319

Name:	us-gaap_EffectiveIncomeTaxRateReconciliationNondeductibleExpenseImpairmentLosses
Namespace Prefix:	us-gaap_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

Income Taxes (Details) $ in Millions, $ in Billions	6 Months Ended
Income Taxes (Details) $ in Millions, $ in Billions	Jun. 30, 2019	Jun. 30, 2018	Aug. 31, 2016 USD ($)	Aug. 31, 2016 MXN ($)
Effective Income Tax Rate Reconciliation, Percent [Abstract]
Effective income tax rate, continuing operations	(11.60%)	79.60%
Nondeductible goodwill impairment charge	(24.80%)
Mexican Tax Authority \| Tax Year 2010
Income Tax Contingency [Line Items]
Number of subsidiaries in a tax assessment			1	1
Tax assessment			$ 157	$ 3