To make a bold, decisive move or take the plunge—undertake a risky or costly action after making up one's mind (idiomatic; derived from the image of jumping off the Kiyomizu Temple veranda).
家を建て替えるために、彼は清水の舞台から飛び降りるつもりで借金をした。
To rebuild the house, he took the plunge and went into debt.
新しい事業を始めるには清水の舞台から飛び降りる覚悟が必要だ。
To start a new business you need the resolve to take the plunge.
会社は清水の舞台から飛び降りる形で大型投資を行った。
The company made a large investment, essentially taking a bold leap.