  In light of the recent discovery by the ATLAS and CMS experiments at the
Large Hadron Collider (LHC) of a Higgs-like particle with a narrow mass range
of 125-126 GeV, we perform an updated analysis on one of the popular scalar
dark matter models, the Inert Higgs Doublet Model (IHDM). We take into account
in our likelihood analysis of various experimental constraints, including
recent relic density measurement, dark matter direct and indirect detection
constraints as well as the latest collider constraints on the invisible decay
width of the Higgs boson and monojet search at the LHC. It is shown that if the
invisible decay of the standard model Higgs boson is open, LHC as well as
direct detection experiments like LUX and XENON100 could put stringent limits
on the Higgs boson couplings to dark matter. We find that the most favoured
parameter space for IHDM corresponds to dark matter with a mass less than 100
GeV or so. In particular, the best-fit points are at the dark matter mass
around 70 GeV where the invisible Higgs decay to dark matter is closed. Scalar
dark matter in the higher mass range of 0.5-4 TeV is also explored in our
study. Projected sensitivities for the future experiments of monojet at LHC-14,
XENON1T and AMS-02 one year antiproton flux are shown to put further
constraints on the existing parameter space of IHDM.
