Definition of long account in English:
long account
noun
1(A statement showing) a considerable sum of money due; now chiefly figurative.
2The action or an act of accounting to God after death for (one's) conduct in life; the Last Judgement (now rare).
Origin
Mid 17th century; earliest use found in George Havers (fl. 1665).
Are You Learning English? Here Are Our Top English Tips