Stockholders' Equity	3 Months Ended
Mar. 31, 2019
Equity [Abstract]
Stockholders' Equity	Stockholders’ Equity Preferred Stock. The Corporation is authorized to issue 10 million shares of preferred stock without par value. The Board of Directors is authorized to fix the particular designations, preferences and relative, participating, optional and other special rights and qualifications, limitations or restrictions for each series of preferred stock issued. As of March 31, 2019, the Corporation had issued and outstanding 500,000 depositary shares, each representing a 1/100th ownership interest in a share of Series D Non-Cumulative Perpetual Preferred Stock (the “Series D Preferred Stock”) issued in August 2016. Equity related to Series D Preferred Stock as of March 31, 2019 and December 31, 2018 was $493.5 million. Shares of the Series D Preferred Stock have no par value and a liquidation preference of $100,000 (equivalent to $1,000 per depositary share). Dividends on the Series D Preferred Stock, which are not mandatory, accrue and are payable on the liquidation preference amount, on a non-cumulative basis, at a rate per annum equal to (i) 4.60% from the original issue date of the Series D Preferred Stock to but excluding October 1, 2026; and (ii) a floating rate equal to Three-Month LIBOR plus 3.202% from and including October 1, 2026. Fixed rate dividends are payable in arrears on the 1st day of April and October of each year, through and including October 1, 2026, and floating rate dividends will be payable in arrears on the 1st day of January, April, July and October of each year, commencing on January 1, 2027. On January 22, 2019, the Corporation declared a cash dividend of $2,300 per share of Series D Preferred Stock payable on April 1, 2019, to stockholders of record as of March 15, 2019. As of March 31, 2019, the Corporation also had issued and outstanding 16 million depositary shares, each representing 1/1000th ownership interest in a share of Series C Non-Cumulative Perpetual Preferred Stock (“Series C Preferred Stock”), issued in August 2014. Equity related to Series C Preferred Stock as of March 31, 2019 and December 31, 2018 was $388.5 million. Series C Preferred Stock has no par value and has a liquidation preference of $25,000 (equivalent to $25 per depositary share). Dividends on the Series C Preferred Stock, which are not mandatory, accrue and are payable on the liquidation preference amount, on a non-cumulative basis, quarterly in arrears on the first day of January, April, July and October of each year, at a rate per annum equal to 5.85%. On January 22, 2019, the Corporation declared a cash dividend of $365.625 per share of Series C Preferred Stock payable on April 1, 2019, to stockholders of record as of March 15, 2019. Common Stock. During the three months ended March 31, 2019, the Corporation repurchased 2,850,152 shares of common stock, including 510,011 shares withheld related to share-based compensation, at a total cost of $257.4 million ($90.31 average price per share). The Corporation’s current stock repurchase authorization to repurchase up to 25.0 million shares was approved by the Board of Directors in July 2018. Shares are repurchased by the Corporation, to, among other things, manage the Corporation’s capital levels. Repurchased shares are used for general purposes, including the issuance of shares under stock option and other incentive plans. The repurchase authorization approved by the Board of Directors has no expiration date. Under the Corporation’s 2018 Capital Plan, which was reviewed without objection by the Federal Reserve, the Corporation may repurchase up to $272.2 million of common stock after March 31, 2019 through June 30, 2019.

Stockholders’ Equity

Preferred Stock. The Corporation is authorized to issue 10 million shares of preferred stock without par value. The Board of Directors is authorized to fix the particular designations, preferences and relative, participating, optional and other special rights and qualifications, limitations or restrictions for each series of preferred stock issued.

As of March 31, 2019, the Corporation had issued and outstanding 500,000 depositary shares, each representing a 1/100th ownership interest in a share of Series D Non-Cumulative Perpetual Preferred Stock (the “Series D Preferred Stock”) issued in August 2016. Equity related to Series D Preferred Stock as of March 31, 2019 and December 31, 2018 was $493.5 million. Shares of the Series D Preferred Stock have no par value and a liquidation preference of $100,000 (equivalent to $1,000 per depositary share).

Dividends on the Series D Preferred Stock, which are not mandatory, accrue and are payable on the liquidation preference amount, on a non-cumulative basis, at a rate per annum equal to (i) 4.60% from the original issue date of the Series D Preferred Stock to but excluding October 1, 2026; and (ii) a floating rate equal to Three-Month LIBOR plus 3.202% from and including October 1, 2026. Fixed rate dividends are payable in arrears on the 1st day of April and October of each year, through and including October 1, 2026, and floating rate dividends will be payable in arrears on the 1st day of January, April, July and October of each year, commencing on January 1, 2027. On January 22, 2019, the Corporation declared a cash dividend of $2,300 per share of Series D Preferred Stock payable on April 1, 2019, to stockholders of record as of March 15, 2019.

As of March 31, 2019, the Corporation also had issued and outstanding 16 million depositary shares, each representing 1/1000th ownership interest in a share of Series C Non-Cumulative Perpetual Preferred Stock (“Series C Preferred Stock”), issued in August 2014. Equity related to Series C Preferred Stock as of March 31, 2019 and December 31, 2018 was $388.5 million. Series C Preferred Stock has no par value and has a liquidation preference of $25,000 (equivalent to $25 per depositary share).

Dividends on the Series C Preferred Stock, which are not mandatory, accrue and are payable on the liquidation preference amount, on a non-cumulative basis, quarterly in arrears on the first day of January, April, July and October of each year, at a rate per annum equal to 5.85%. On January 22, 2019, the Corporation declared a cash dividend of $365.625 per share of Series C Preferred Stock payable on April 1, 2019, to stockholders of record as of March 15, 2019.

Common Stock. During the three months ended March 31, 2019, the Corporation repurchased 2,850,152 shares of common stock, including 510,011 shares withheld related to share-based compensation, at a total cost of $257.4 million ($90.31 average price per share). The Corporation’s current stock repurchase authorization to repurchase up to 25.0 million shares was approved by the Board of Directors in July 2018. Shares are repurchased by the Corporation, to, among other things, manage the Corporation’s capital levels. Repurchased shares are used for general purposes, including the issuance of shares under stock option and other incentive plans. The repurchase authorization approved by the Board of Directors has no expiration date.

Under the Corporation’s 2018 Capital Plan, which was reviewed without objection by the Federal Reserve, the Corporation may repurchase up to $272.2 million of common stock after March 31, 2019 through June 30, 2019.