Restrictions on Cash and Due from Banks, Securities, Loans and Dividends	12 Months Ended
Dec. 31, 2016
Restricted Cash and Investments [Abstract]
Restrictions on Cash and Due from Banks, Securities, Loans and Dividends	Restrictions on Cash and Due from Banks, Securities, Loans and Dividends Federal Reserve regulations require the Bank to maintain reserve balances based on the types and amounts of deposits received. The required reserve balances were $761 million and $565 million at December 31, 2016 and 2015, respectively. See Note 3 to these consolidated financial statements for the carrying amounts of securities that were pledged as collateral to secure public and trust deposits and for other transactions as required by contract or law. See Note 11 to these consolidated financial statements for the carrying amounts of loans and securities that were pledged as collateral for borrowings, including those pledged to the Federal Reserve Bank and FHLB. The Federal Reserve Act restricts the amount and the terms of both credit and non-credit transactions between a bank and its non-bank affiliates. Such transactions may not exceed 10% of the bank's capital and surplus (which for this purpose represents Tier 1 and Tier 2 capital, as calculated under the risk-based capital guidelines, plus the balance of the allowance for loan losses excluded from Tier 2 capital) with any single non-bank affiliate and 20% of the bank's capital and surplus with all its non-bank affiliates. Transactions that are extensions of credit may require collateral to be held to provide added security to the bank. See Note 19 to these consolidated financial statements for further discussion of risk-based capital. At December 31, 2016, $251 million of notes payable remained outstanding from Bankers Commercial Corporation, and $111 million remained outstanding from all other non-bank affiliates. The declaration of a dividend by the Bank to the Company is subject to the approval of the OCC if the total of all dividends declared in the current calendar year plus the preceding two years exceeds the Bank's total net income in the current calendar year plus the preceding two years. The payment of dividends is also limited by minimum capital requirements imposed on national banks by the OCC.

Restrictions on Cash and Due from Banks, Securities, Loans and Dividends

Federal Reserve regulations require the Bank to maintain reserve balances based on the types and amounts of deposits received. The required reserve balances were $761 million and $565 million at December 31, 2016 and 2015, respectively.

See Note 3 to these consolidated financial statements for the carrying amounts of securities that were pledged as collateral to secure public and trust deposits and for other transactions as required by contract or law. See Note 11 to these consolidated financial statements for the carrying amounts of loans and securities that were pledged as collateral for borrowings, including those pledged to the Federal Reserve Bank and FHLB.

The Federal Reserve Act restricts the amount and the terms of both credit and non-credit transactions between a bank and its non-bank affiliates. Such transactions may not exceed 10% of the bank's capital and surplus (which for this purpose represents Tier 1 and Tier 2 capital, as calculated under the risk-based capital guidelines, plus the balance of the allowance for loan losses excluded from Tier 2 capital) with any single non-bank affiliate and 20% of the bank's capital and surplus with all its non-bank affiliates. Transactions that are extensions of credit may require collateral to be held to provide added security to the bank. See Note 19 to these consolidated financial statements for further discussion of risk-based capital. At December 31, 2016, $251 million of notes payable remained outstanding from Bankers Commercial Corporation, and $111 million remained outstanding from all other non-bank affiliates.

The declaration of a dividend by the Bank to the Company is subject to the approval of the OCC if the total of all dividends declared in the current calendar year plus the preceding two years exceeds the Bank's total net income in the current calendar year plus the preceding two years. The payment of dividends is also limited by minimum capital requirements imposed on national banks by the OCC.