Equity (Schedule of Stockholders Equity) (Details) (USD $) In Billions, except Share data, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Feb. 26, 2015
Schedule of Stockholders Equity [Line Items]
Stockholders' Equity Note, Stock Split, Conversion Ratio	310
Common Stock, Par or Stated Value Per Share	$ 0.01
Common Stock, Shares Authorized	1,100,000,000us-gaap_CommonStockSharesAuthorized
Common Stock, Shares, Outstanding, beginning of period	479,767,470us-gaap_CommonStockSharesOutstanding	412,600,700us-gaap_CommonStockSharesOutstanding	412,600,700us-gaap_CommonStockSharesOutstanding
Stock Issued During Period, Shares, New Issues	368,569	0	0
Stock Issued During Period, Shares, Conversion of Convertible Securities	0	67,166,770	0
Common Stock, Shares, Issued	480,136,039us-gaap_CommonStockSharesIssued	479,767,470us-gaap_CommonStockSharesIssued	412,600,700us-gaap_CommonStockSharesIssued
Treasury Stock, Shares, Acquired	(41,148)us-gaap_TreasuryStockSharesAcquired	0us-gaap_TreasuryStockSharesAcquired	0us-gaap_TreasuryStockSharesAcquired
Common Stock, Shares, Outstanding, end of period		479,767,470us-gaap_CommonStockSharesOutstanding	412,600,700us-gaap_CommonStockSharesOutstanding
Treasury Stock, Shares	41,148us-gaap_TreasuryStockShares	0us-gaap_TreasuryStockShares	0us-gaap_TreasuryStockShares
Common Stock, Value, Issued	$ 1.3us-gaap_CommonStockValue
Entity Common Stock, Shares Outstanding	480,094,891dei_EntityCommonStockSharesOutstanding			481,501,265dei_EntityCommonStockSharesOutstanding

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Indicate number of shares or other units outstanding of each of registrant's classes of capital or common stock or other ownership interests, if and as stated on cover of related periodic report. Where multiple classes or units exist define each class/interest by adding class of stock items such as Common Class A [Member], Common Class B [Member] or Partnership Interest [Member] onto the Instrument [Domain] of the Entity Listings, Instrument.

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Face amount or stated value per share of common stock.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Aggregate par or stated value of issued nonredeemable common stock (or common stock redeemable solely at the option of the issuer). This item includes treasury stock repurchased by the entity. Note: elements for number of nonredeemable common shares, par value and other disclosure concepts are in another section within stockholders' equity.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Number of shares issued during the period as a result of the conversion of convertible securities.

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