|
Stockholders' equity (Details) (USD $)
|
12 Months Ended | |
|---|---|---|
|
Dec. 31, 2013
|
Dec. 31, 2012
|
|
| Preferred stock | ||
| Preferred stock, shares authorized (in shares) | 15,000,000 | 15,000,000 |
| Preferred stock, par value (in dollars per share) | $ 0.001 | $ 0.001 |
| Common stock | ||
| Common stock, par value (in dollars per share) | $ 0.001 | $ 0.001 |
| Common stock, shares authorized (in shares) | 100,000,000 | 100,000,000 |
| Common stock, voting rights | 1 | |
| Treasury Stock [Abstract] | ||
| Stock repurchased during period, value | $ 213,000 | $ 5,906,000 |
|
Senior Managment [Member]
|
||
| Treasury Stock [Abstract] | ||
| Stock repurchased as part of stock swap (in shares) | 14,472 | |
| Stock repurchased as part of stock swap, value | 287,000 | |
|
Stock Repurchase Plan of 2012 [Member]
|
||
| Treasury Stock [Abstract] | ||
| Stock Repurchase Program, Authorized Amount | 35,000,000 | |
| Stock repurchased during period (in shares) | 398,481 | |
| Stock repurchased during period, value | $ 5,800,000 | |