How does a Bank's Balance Sheet always make it Equal? What if it doesn't?

-Usually, if the Value of a Bank's Asset Falls, the Bank's Capital is also Reduced by the Same Amount -If a Borrower had Defaulted on a Loan, the Value of that Loan as an Asset would Fall, and the Banks Level of Capital would also Fall -If the Total Value of the Bank's Asset fell by a Large Amount, the Bank could 'Run Out of Capital' making the Bank Insolvent. This usually leads to a Collapse in the Bank as Central Banks don't Lend to Insolvent Banks