Accounts Payable and Accrued Expenses (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Payables and Accruals [Abstract]
Trade accounts payable	$ 402	$ 127
Client deposits	625	564
Accrued compensation and benefits	310	199
Other accrued expenses	1,564	256
Total	$ 2,901	$ 1,146

Contract With Customer, Liability, Customer Deposits, Current

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- Definition

Sum of the carrying values as of the balance sheet date of obligations incurred through that date and due within one year (or the operating cycle, if longer), including liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received, taxes, interest, rent and utilities, accrued salaries and bonuses, payroll taxes and fringe benefits.

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Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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- Definition

Carrying value as of the balance sheet date of obligations, excluding pension and other postretirement benefits, incurred through that date and payable for perquisites provided to employees pertaining to services received from them. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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Amount of expenses incurred but not yet paid classified as other, due within one year or the normal operating cycle, if longer.

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