We present precise measurements of CP and CPT symmetry based on the full dataset of K to 2pi decays collected by the KTeV experiment at FNAL. We measure the direct CP violation parameter Re(epsilon/epsilon) = (19.2 pm 2.1)x10-4. We also report the KL-KS mass difference, the KS lifetime, the phase of epsilon, and the phase difference (phi00)-(phi+-). These results are consistent with other experimental results and with CPT symmetry.