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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.

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The cash inflow associated with the amount received from the sale of a portion of the company's business, for example a segment, division, branch or other business, during the period.

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The cash outflow during the period from the repayment of aggregate short-term and long-term debt. Excludes payment of capital lease obligations.

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Amount of stock repurchase plan authorized.

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The remaining number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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Subsequent Events (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands			2 Months Ended		12 Months Ended
	Jan. 31, 2018	Jan. 02, 2018	Mar. 12, 2018	Feb. 28, 2018	Dec. 31, 2017	Feb. 08, 2018
Subsequent events
Proceeds from sale of business					$ 300
Outstanding principal amount					$ 1,431,059
LIBOR rate
Subsequent events
Spread on variable rate basis (as a percent)					1.25%
Senior secured term loan
Subsequent events
Repayments of debt		$ 26,000
Outstanding principal amount		$ 624,000
Senior secured term loan \| LIBOR rate
Subsequent events
Spread on variable rate basis (as a percent)		3.25%
Senior Secured Credit Facility
Subsequent events
Repayments of debt		$ 250,000
Subsequent Events \| Class A
Subsequent events
Total Number of Shares Purchased as Part of Publicly Announced Plans or Programs(1)			375,000	375,000
Average Price Paid per Share			$ 29.27	$ 29.27
Approximate Dollar Value of Shares that May Yet Be Purchased Under the Plans or Programs			39,023,750	39,023,750
New share repurchase program authorized						$ 50,000
Dividends declared (in dollars per share)	$ 0.24
Subsequent Events \| ICE \| BondPoint
Subsequent events
Proceeds from sale of business		$ 400,000