Income Taxes	6 Months Ended
Jun. 30, 2019
Income Tax Disclosure [Abstract]
Income Taxes	21. Income Taxes The six months ended June 30, 2019 and 2018 income tax expense included $22 million and $58 million, respectively, of discrete tax benefits related to stock-based compensation awards that vested in the first quarter of each respective year.

The entire disclosure for income taxes. Disclosures may include net deferred tax liability or asset recognized in an enterprise's statement of financial position, net change during the year in the total valuation allowance, approximate tax effect of each type of temporary difference and carryforward that gives rise to a significant portion of deferred tax liabilities and deferred tax assets, utilization of a tax carryback, and tax uncertainties information.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 740
-URI http://asc.fasb.org/topic&trid=2144680

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