CONSOLIDATED FINANCIAL STATEMENTS Summary of Changes in Financial Statement Presentation (Details) $ in Millions	3 Months Ended
Jun. 30, 2018 USD ($)
Changes in Financial Statement Presentation [Abstract]
Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect	$ (254)

Tax Cuts and Jobs Act, Reclassification from AOCI to Retained Earnings, Tax Effect - Amount of increase (decrease) in accumulated other comprehensive income (AOCI) for the reclassification to retained earnings of tax effect from remeasurement of deferred tax pursuant to Tax Cuts and Jobs Act

No definition available.

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