From the Fed: Minutes of the Federal Open Market Committee, September 19-20, 2017. Excerpts:

In their discussion of monetary policy, all participants agreed that the economy had evolved broadly as they had anticipated at the time of the June meeting and that the incoming data had not materially altered the medium-term economic outlook. Consistent with those assessments, participants saw it as appropriate, at this meeting, to announce implementation of the plan for reducing the Federal Reserve's securities holdings that the Committee released in June. Many underscored that the reduction in securities holdings would be gradual and that financial market participants appeared to have a clear understanding of the Committee's planned approach for a gradual normalization of the size of the Federal Reserve's balance sheet. Consequently, participants generally expected that any reaction in financial markets to the start of balance sheet normalization would likely be limited.
...
Consistent with the expectation that a gradual rise in the federal funds rate would be appropriate, many participants thought that another increase in the target range later this year was likely to be warranted if the medium-term outlook remained broadly unchanged. Several others noted that, in light of the uncertainty around their outlook for inflation, their decision on whether to take such a policy action would depend importantly on whether the economic data in coming months increased their confidence that inflation was moving up toward the Committee's objective. A few participants thought that additional increases in the federal funds rate should be deferred until incoming information confirmed that the low readings on inflation this year were not likely to persist and that inflation was clearly on a path toward the Committee's symmetric 2 percent objective over the medium term. All agreed that they would closely monitor and assess incoming data before making any further adjustment to the federal funds rate.
emphasis added