XML 39 R32.htm IDEA: XBRL DOCUMENT
v2.4.0.8

Shareholders’ equity (Tables) | 6 Months Ended
--- | ---
Jun. 30, 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 the six months ended June 30, 2014 and 2013.
Common and Preferred Stock Activity: | Preferred stock |  | Common stock
(in shares) | Series A convertible |  | Treasury | Outstanding
Beginning balance as of December 31, 2013 | 79,620 |  |  | 4,786,521 |  | 88,710,277 |
Conversion of convertible preferred stock | (394 | ) |  | — |  | 39,455 |
Issuance for share-based compensation plans | — |  |  | — |  | 55,029 |
Ending balance as of June 30, 2014 | 79,226 |  |  | 4,786,521 |  | 88,804,761 |
Beginning balance as of December 31, 2012 | 80,283 |  |  | 4,786,521 |  | 88,548,637 |
Conversion of convertible preferred stock | (199 | ) |  | — |  | 19,864 |
Issuance for share-based compensation plans | — |  |  | — |  | 34,208 |
Ending balance as of June 30, 2013 | 80,084 |  |  | 4,786,521 |  | 88,602,709 |

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