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Preferred and Common Stock - Schedule of Share Activity (Detail) |  |  |  |  | 12 Months Ended
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Dec. 31, 2013 | Dec. 31, 2012 | Dec. 31, 2011 | Dec. 31, 2010 | Dec. 31, 2013 Outstanding Stock [Member] | Dec. 31, 2012 Outstanding Stock [Member] | Dec. 31, 2011 Outstanding Stock [Member] | Dec. 31, 2013 Treasury Stock [Member] | Dec. 31, 2012 Treasury Stock [Member] | Dec. 31, 2011 Treasury Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |  |  |  |  |  |  |  |  |  |
Treasury stock, beginning balance | 106,895,705 | 110,694,604 | 113,494,491 | 119,362,029 |  |  |  |  |  |
Conversion of convertible notes |  |  |  |  | 310 |  |  |  |  |
Private placement |  |  |  |  |  |  | 36,518,563 |  |  |
Issued for stock-based compensation plans |  |  |  |  | 3,798,899 | 2,799,887 | 5,867,538 | (3,798,899) | (2,799,887) | (5,867,538)
Treasury stock, ending balance | 106,895,705 | 110,694,604 | 113,494,491 | 119,362,029 |  |  |  |  |  |
Common Stock Outstanding, beginning balance | 1,071,011,162 | 1,067,211,953 | 1,064,412,066 | 1,022,025,965 |  |  |  |  |  |
Common Stock Outstanding, ending balance | 1,071,011,162 | 1,067,211,953 | 1,064,412,066 | 1,022,025,965 |  |  |  |  |  |

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- Definition Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.29) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 30 -Article 5 + Details
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- Definition Number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP), net of any shares forfeited. Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 04 -Article 3 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=6928386&loc=d3e21463-112644 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 505 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.3-04) -URI http://asc.fasb.org/extlink&oid=27012166&loc=d3e187085-122770 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 02 -Paragraph 29, 30 -Article 5 + Details
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