Derivatives and Hedging - Net investment hedge (Details) - Term Loan B - USD ($) $ in Millions	Dec. 31, 2018	Dec. 31, 2017
Derivatives and Hedging
Long-term debt	$ 1,980	$ 2,000
Net investment hedge
Derivatives and Hedging
Long-term debt	271	271
Long-term debt, excluding capital leases	$ 256	$ 298

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

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