CONSOLIDATED STATEMENT OF CASH FLOWS (Parenthetical) - USD ($) $ in Millions	3 Months Ended	12 Months Ended
Dec. 31, 2017	Dec. 31, 2017
Statement of Cash Flows [Abstract]
Impact of non-cash charge related to Tax Reform	$ 22,600	$ 22,594

Tax Cuts And Jobs Act Of 2017, Complete Including Provisional Accounting, Provisional Income Tax Expense (Benefit)

No definition available.

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