Additional Financial Information (Components of Other Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2019	Jun. 30, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accrued non-current pension/postretirement liabilities	$ 547	$ 543
Non-current operating lease liabilities	429	0
Other non-current liabilities	336	356
Total other liabilities	$ 1,312	$ 899

Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of liabilities classified as other, due after one year or the normal operating cycle, if longer.

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Obligations not otherwise itemized or categorized in the footnotes to the financial statements that are expected to be paid after one year (or the normal operating cycle, if longer), from the balance sheet date.

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Amount of liability, recognized in statement of financial position, for defined benefit pension and other postretirement plans, classified as noncurrent.

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