XML 157 R38.htm IDEA: XBRL DOCUMENT
v2.4.1.9

Shareholders’ equity (Tables) | 12 Months Ended
--- | ---
Dec. 31, 2014
Stockholders' Equity Note [Abstract] |
Common and Preferred Stock Activity | The Common and Preferred Stock Activity table below contains additional information about preferred stock conversions during 2014, 2013 and 2012:
Common and Preferred Stock Activity: | Preferred stock | Common stock
(in shares) | Series A convertible | Treasury | Outstanding
Balance as of December 31, 2011 | 80,718 |  | 4,386,521 |  | 88,844,327 |
Repurchase of common stock | — |  | 400,000 |  | (400,000 | )
Conversion of convertible preferred stock | (435 | ) | — |  | 43,556 |
Issuance for share-based compensation plans | — |  | — |  | 60,754 |
Balance as of December 31, 2012 | 80,283 |  | 4,786,521 |  | 88,548,637 |
Conversion of convertible preferred stock | (663 | ) | — |  | 66,244 |
Issuance for share-based compensation plans | — |  | — |  | 95,396 |
Balance as of December 31, 2013 | 79,620 |  | 4,786,521 |  | 88,710,277 |
Conversion of convertible preferred stock | (1,479 | ) | — |  | 147,952 |
Issuance for share-based compensation plans | — |  | — |  | 206,353 |
Balance as of December 31, 2014 | 78,141 |  | 4,786,521 |  | 89,064,582 |

X
- Definition Tabular disclosure of the change in preferred stock, treasury stock and common stock outstanding. + References No definition available. + Details
Name: | cenx_ScheduleOfCommonandPreferredStockRollForwardTableTextBlock
Namespace Prefix: | cenx_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_StockholdersEquityNoteAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration