|
Significant accounting policies (Details)
In Thousands, unless otherwise specified |
3 Months Ended | 12 Months Ended | ||||||
|---|---|---|---|---|---|---|---|---|
|
Sep. 30, 2012
|
Jun. 30, 2012
|
Mar. 31, 2012
|
Sep. 30, 2011
|
Jun. 30, 2011
|
Mar. 31, 2011
|
Dec. 31, 2012
|
Dec. 31, 2011
|
|
| Schedule of Weighted Average Number of Shares [Line Items] | ||||||||
| Basic weighted average common shares outstanding | 82,183 | 81,965 | ||||||
| Basic weighted average preferred shares outstanding | 32,667 | 32,667 | ||||||
| Basic weighted average shares outstanding | 114,735 | 114,547 | 114,473 | 114,685 | 114,673 | 114,642 | 114,850 | 114,632 |
| Dilutive effect of stock options | 4,747 | 0 | ||||||
| Diluted weighted average shares outstanding | 119,973 | 120,087 | 119,997 | 114,685 | 114,673 | 114,642 | 119,597 | 114,632 |