Subsequent Event	12 Months Ended
Dec. 31, 2017
Subsequent Events [Abstract]
Subsequent Event	Subsequent Event On February 8, 2018, CSC redeemed all of its outstanding 1.500% Senior Notes due March 10, 2018. The aggregate principal amount of the notes was $625 million.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

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