| 2013 | 2012 | 2011 | ||||||||
| Balance at beginning of year | $ | 4,129 | $ | 2,522 | $ | 2,274 | ||||
| Gross increases | ||||||||||
| Tax position of current year | 632 | 145 | 160 | |||||||
| Tax positions of prior years | 506 | 2,988 | 763 | |||||||
| Gross decreases | ||||||||||
| Statute expirations | (264) | (713) | (595) | |||||||
| Settlements | 0 | (404) | 0 | |||||||
| Tax positions of prior years | 0 | (409) | (80) | |||||||
| Balance at December 31 | $ | 5,003 | $ | 4,129 | $ | 2,522 | ||||