215 ILCS 5/145
When any company is required by the laws of this State or of any state or country, or by other competent authority, to make a deposit with an insurance supervising official or other financial officer and the company desires to make such deposit in this State the Director shall accept such deposit, if made in securities authorized for investment by Article VIII of this Code. So long as the company continues solvent and complies with the laws of this State it may collect the income on such securities. The company may substitute therefor other like securities as prescribed by this Code for deposit. If the value of securities deposited by any company shall decline below the amount so required, the company shall make a further deposit.
215 ILCS 5/145