Degrees of Freedom in SAS Proc MIXED

Below is a SAS proc Mixed code generated by JMP. Both JMP and SAS give me a confidence interval for the variance components (in the table "covariance parameter estimates"). I would like the degrees of freedom in the output, or at least a formula to calculate them. Can anyone tell me where that would be?

DATA Untitled; INPUT  x y Batch &$; Lines;
0  107.2109269  4  
3  106.3777088  4  
6  103.8625117  4  
9  103.7524023  4  
12  101.6895595  4  
18  104.4145268  4  
24  100.6606813  4  
0  107.6603635  5  
3  105.9161433  5  
6  106.0260339  5  
9  104.660272  5  
12  102.5820776  5  
18  103.7961511  5  
24  101.2887124  5  
0  109.2066284  6  
3  106.9341754  6  
6  106.6141445  6  
9  106.8234541  6  
12  104.7778902  6  
18  106.0184734  6  
24  102.9822743  6  
;
RUN;

PROC MIXED ASYCOV NOBOUND  DATA=Untitled ALPHA=0.05;
CLASS Batch;
MODEL  y =  x/ SOLUTION DDFM=KENWARDROGER;
RANDOM Batch / SOLUTION ;
RUN;