Subsequent Events	12 Months Ended
Dec. 31, 2018
Subsequent Events [Abstract]
Subsequent Events	Subsequent Events Senior Notes Activity On February 15, 2019, we completed the issuance of $500 million of 3.625% senior unsecured notes due 2024 and $550 million of 4.125% senior unsecured notes due 2029. On February 15, 2019, we also announced the redemption of $600 million of 4.125% senior unsecured notes due 2019 and $450 million of 6.125% senior unsecured notes due 2020. Preferred Stock Activity On February 21, 2019, we announced that we elected to effect the conversion of all of the outstanding Series I Preferred Stock. Each share of convertible preferred stock will be converted into 0.8857 shares of common stock on February 28, 2019.

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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