Additional Financial Information (Components of Other Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Jun. 30, 2020
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Accrued non-current pension/postretirement liabilities	$ 704	$ 709
Non-current operating lease liabilities	413	452
Other non-current liabilities	352	321
Total other liabilities	$ 1,469	$ 1,482

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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