Subsequent Events	3 Months Ended
Mar. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events As of May 3, 2018, the Company had repurchased 0.2 million shares of common stock, at an average share price of $162.32.

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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