XML 120 R106.htm IDEA: XBRL DOCUMENT v3.6.0.2
Stockholders' Equity Stockholders' Equity (Summary of unvested restricted stock awards) (Details) - Restricted Stock Units (RSUs) - $ / shares
3 Months Ended 12 Months Ended
Mar. 31, 2015
Dec. 31, 2016
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Number of Shares [Roll Forward]    
Unvested at beginning of year (in shares)   202,000
Awards (in shares) 16,900 17,960
Vestings (in shares)   (66,000)
Cancellations (in shares)   (91,000)
Unvested at end of year (in shares)   63,000
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Nonvested, Weighted Average Grant Date Fair Value [Roll Forward]    
Unvested at beginning of year   $ 20.64
Awards   20.27
Vestings   20.78
Cancellations   20.17
Unvested at beginning of year   $ 21.07