  We study the size and structure of globular clusters (GC) systems of 118
early-type galaxies from the NGVS, MATLAS, and ACSVCS surveys. Fitting S\'ersic
profiles, we investigate the relationship between effective radii of GC systems
($R_{e, \rm gc}$) and galaxy properties. GC systems are 2--4 times more
extended than host galaxies across the entire stellar mass range of our sample
($10^{8.3} < M_* < 10^{11.6}~M_{\odot}$). The relationship between $R_{e, \rm
gc}$ and galaxy stellar mass exhibits a characteristic "knee" at a stellar mass
of $M_p \simeq 10^{10.8}$, similar to galaxy $R_e$--stellar mass relationship.
We present a new characterization of the traditional blue and red GC color
sub-populations, describing them with respect to host galaxy $(g'-i')$ color
($\Delta_{gi}$): GCs with similar colors to their hosts have a "red"
$\Delta_{gi}$, and those significantly bluer GCs have a "blue" $\Delta_{gi}$.
The GC populations with red $\Delta_{gi}$, even in dwarf galaxies, are twice as
extended as the stars, suggesting that formation or survival mechanisms favor
the outer regions. We find a tight correlation between $R_{e, \rm gc}$ and the
total number of GCs, with intrinsic scatter $\lesssim 0.1$ dex spanning two and
three orders of magnitude in size and number, respectively. This holds for both
red and blue subpopulations, albeit with different slopes. Assuming that
$N_{GC, Total}$ correlates with $M_{200}$, we find that the red GC systems have
effective radii of roughly 1-5\% $R_{\rm 200}$, while the blue GC systems in
massive galaxies can have sizes as large as $\sim$10\% $R_{\rm 200}$.
Environmental dependence on $R_{e, \rm gc}$ is also found, with lower density
environments exhibiting more extended GC systems at fixed mass.
