Revenue Recognition - Accounts Receivable (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018
Accounts receivable
Customer and agents	$ 989	$ 992
Other	127	107
Accounts receivable from contract with customer
Accounts receivable
Customer and agents	984	987
Other	107	73
Total	$ 1,091	$ 1,060

Amount, after allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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