XML 16 R54.htm IDEA: XBRL DOCUMENT v2.4.0.6
Summary of Significant Accounting Policies (Details 4)
 1 Months Ended 12 Months Ended
Aug. 31, 2012
Mar. 31, 2012
Feb. 29, 2012
Aug. 31, 2011
Mar. 31, 2011
Dec. 31, 2012
Dec. 31, 2011
Share-based payments and stock-based compensation              
Shares of common stock reserved for issuance upon exercise of all future stock option grants, SARS and grants of restricted shares under the 2008 Equity Plan           1,270,744  
Issuance of employee LTI shares (in shares)   111,790     94,966 111,790 94,966
Period of restriction on trade for shares issued to employees under the Primoris Long-term Retention Plan           6 months  
Shares of common stock issued as a part of quarterly compensation of non-employee members of the Board of Directors 15,280   12,395 14,825   27,675 14,825
Period of restriction on trade for shares issued to non-employee members of the board of directors under the Primoris Long-term Retention Plan           1 year  
Minimum
              
Property and equipment              
Estimated useful lives of the related assets           3 years  
Maximum
              
Property and equipment              
Estimated useful lives of the related assets           30 years