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We propose a 20 orbit WFC3-IR campaign in the environs of HST Frontier Field (HFF) clusters to obtain the most comprehensive view to date of the intracluster stellar population and total baryon content in massive galaxy clusters. Our program builds upon the existing investment in the HFFs to provide contiguous coverage out to virgul3 Mpc from the cluster center. We will use these data sets to make the first determination of the total stellar content comma including the intracluster light (ICL) comma out to >0.65 r200 for each of the HFF clusters comma directly constraining the extent to which the cluster galaxy population is altered by processes leading to ICL formation comma and the radii over which these process are important. We will also compare the spatial distributions of the ICL comma intracluster medium comma galaxies comma and dark matter within the central 300 kpc to establish whether the observed low scatter in the radial gas-to-stellar ratio masks underlying small scale variations due to various processeses such as ram pressure stripping comma winds comma and tidal stripping. This comparison will also test the recent assertion that the ICL is a highly robust tracer of the underlying mass distribution (based on work at smaller radii) comma and whether the ICL can be used by future missions such as Euclid and Roman to measure cluster mass distributions. Finally comma we expect to be able to detect signatures of the splashback radius in at least some of these clusters comma which we will use in conjunction with weak lensing masses to measure cluster mass accretion rates. Literature results for the HFF cluster MACS J1149.5+2223 demonstrate the feasibility of this program.