Acquisitions and Other Strategic Initiatives - Total Consideration Relating to Acquisition (Details) - Regulatory Data Corporation $ in Millions	Feb. 13, 2020 USD ($)
Business Acquisition [Line Items]
Cash paid at closing	$ 700
Additional consideration to be paid to sellers in 2020	2
Business Combination, Consideration Transferred, Total	$ 702

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of liabilities incurred by the acquirer as part of consideration transferred in a business combination.

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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