o·ver·ex·tend 
(ō′vər-ĭk-stĕnd)
(ō′vər-ĭk-stĕnd)tr.v. o·ver·ex·tend·ed, o·ver·ex·tend·ing, o·ver·ex·tends
1. To expand or disperse beyond a safe or reasonable limit: overextended their defenses.
2. To obligate (oneself) beyond a limit, especially a financial one.
o′ver·ex·tension n.