Commitments and Contingencies - Commercial Litigation (Details) - Commercial Litigation - TransWeb Corporation $ in Millions	12 Months Ended
Dec. 31, 2016 USD ($) patent claim
Loss contingencies
Payment of legal judgment \| $	$ 27
Number of counts jury did not rule in favor of Transweb \| claim	1
Number of 3M patents unenforceable due to inequitable conduct \| patent	2

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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