[R] p-value from GEE why factor 2*pnorm?

[Carmen Meier]

I got an answer for the other question (thank you)

But there is another question  (I am afraid this is a basic question ...)

In this tread there is a hint hwo to calculate the p-vlue of an GEE:
> _http://finzi.psych.upenn.edu/R/Rhelp02a/archive/74150.html_ 
>
> Then, get the P values using a normal approximation for the 
> distribution of z:
>
> /> 2 * pnorm(abs(coef(summary(fm1))[,5]), lower.tail = FALSE) / 
> (Intercept) TPTLD  0.00000000 0.04190831 

1. why is the result multiplicated  with 2? There is a P-value between 1 and 2
with the results below and multiplicated with 2: 

2*pnorm(c(1.8691945,0.5882351,2.4903091,1.9287802,2.3172983,2.2092593,2.2625959,1.6395695),
lower.tail =TRUE)  

Regards Carmen