Stockholders' Equity	6 Months Ended
Jun. 30, 2017
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. On August 8, 2016, the Corporation issued and sold 500,000 depositary shares (the “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”). 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). The aggregate proceeds from the public offering of the depositary shares, net of underwriting discounts, commissions and offering expenses, were $493.5 million. Dividends on the Series D Preferred Stock, which are not mandatory, will accrue and be 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 will be 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. The Series D Preferred Stock has no maturity date and is redeemable at the Corporation’s option, in whole or in part, on any dividend payment date on or after October 1, 2026. The Series D Preferred Stock is redeemable at the Corporation’s option in whole, but not in part, including prior to October 1, 2026, within 90 days of a regulatory capital treatment event, as described in the Series D Preferred Stock Certificate of Designation. As of June 30, 2017, 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 June 30, 2017 and December 31, 2016 totaled $388.5 million. Series C Preferred Stock has no par value and has a liquidation preference of $25,000 ($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 April 25, 2017, the Corporation declared a cash dividend of $365.625 per share of Series C Preferred Stock payable on July 1, 2017, to stockholders of record as of June 15, 2017. The Series C Preferred Stock has no maturity date and is redeemable at the Corporation’s option, in whole or in part, on any dividend payment date on or after October 1, 2019. The Series C Preferred stock is redeemable at the Corporation’s option, in whole, but not in part, including prior to October 1, 2019, within 90 days of a regulatory capital treatment event, as described in the Series C Preferred Stock Certificate of Designation. Shares of the Series C Preferred Stock and Series D Preferred Stock rank senior to the Corporation’s common stock, and will rank at least equally with any other series of preferred stock it may issue (except for any senior series that may be issued with the requisite consent of the holders of the Series C Preferred Stock and Series D Preferred Stock, respectively) and all other parity stock, with respect to the payment of dividends and distributions upon liquidation, dissolution or winding up. Common Stock. During the three and six months ended June 30, 2017, the Corporation repurchased 1,760,264 shares of common stock, including 4,342 shares withheld related to share-based compensation, at a total cost of $157.6 million ($89.52 average price per share) and 2,571,994 shares of common stock, including 415,211 shares withheld related to share-based compensation, at a total cost of $227.7 million ($88.53 average price per share), respectively. These repurchases were made under the common stock repurchase authorization approved by the Corporation’s Board of Directors in April 2015. On July 18, 2017, this program was terminated and replaced with a new repurchase program, under which the Corporation’s Board of Directors authorized the Corporation to repurchase up to 9.5 million shares of the Corporation’s common stock. Shares repurchased by the Corporation are used for general purposes, including management of the Corporation’s capital levels and the issuance of shares under stock option and other incentive plans of the Corporation. The new repurchase authorization approved by the Board of Directors has no expiration date. Under the Corporation’s 2017 Capital Plan, which was reviewed without objection by the Federal Reserve, the Corporation may repurchase up to $750.0 million of common stock between July 2017 and June 2018.

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.

On August 8, 2016, the Corporation issued and sold 500,000 depositary shares (the “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”). 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). The aggregate proceeds from the public offering of the depositary shares, net of underwriting discounts, commissions and offering expenses, were $493.5 million.

Dividends on the Series D Preferred Stock, which are not mandatory, will accrue and be 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 will be 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.

The Series D Preferred Stock has no maturity date and is redeemable at the Corporation’s option, in whole or in part, on any dividend payment date on or after October 1, 2026. The Series D Preferred Stock is redeemable at the Corporation’s option in whole, but not in part, including prior to October 1, 2026, within 90 days of a regulatory capital treatment event, as described in the Series D Preferred Stock Certificate of Designation.

As of June 30, 2017, 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 June 30, 2017 and December 31, 2016 totaled $388.5 million. Series C Preferred Stock has no par value and has a liquidation preference of $25,000 ($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 April 25, 2017, the Corporation declared a cash dividend of $365.625 per share of Series C Preferred Stock payable on July 1, 2017, to stockholders of record as of June 15, 2017.

The Series C Preferred Stock has no maturity date and is redeemable at the Corporation’s option, in whole or in part, on any dividend payment date on or after October 1, 2019. The Series C Preferred stock is redeemable at the Corporation’s option, in whole, but not in part, including prior to October 1, 2019, within 90 days of a regulatory capital treatment event, as described in the Series C Preferred Stock Certificate of Designation.

Shares of the Series C Preferred Stock and Series D Preferred Stock rank senior to the Corporation’s common stock, and will rank at least equally with any other series of preferred stock it may issue (except for any senior series that may be issued with the requisite consent of the holders of the Series C Preferred Stock and Series D Preferred Stock, respectively) and all other parity stock, with respect to the payment of dividends and distributions upon liquidation, dissolution or winding up.

Common Stock. During the three and six months ended June 30, 2017, the Corporation repurchased 1,760,264 shares of common stock, including 4,342 shares withheld related to share-based compensation, at a total cost of $157.6 million ($89.52 average price per share) and 2,571,994 shares of common stock, including 415,211 shares withheld related to share-based compensation, at a total cost of $227.7 million ($88.53 average price per share), respectively. These repurchases were made under the common stock repurchase authorization approved by the Corporation’s Board of Directors in April 2015. On July 18, 2017, this program was terminated and replaced with a new repurchase program, under which the Corporation’s Board of Directors authorized the Corporation to repurchase up to 9.5 million shares of the Corporation’s common stock. Shares repurchased by the Corporation are used for general purposes, including management of the Corporation’s capital levels and the issuance of shares under stock option and other incentive plans of the Corporation. The new repurchase authorization approved by the Board of Directors has no expiration date.

Under the Corporation’s 2017 Capital Plan, which was reviewed without objection by the Federal Reserve, the Corporation may repurchase up to $750.0 million of common stock between July 2017 and June 2018.