Commitments, Off-Balance Sheet Arrangements, and Legal Proceedings (Tables)

3 Months Ended

Mar. 31, 2016

Commitments and Contingencies Disclosure [Abstract]

Summary of lending-related and other commitments

The following is a summary of lending-related commitments.

	March 31, 2016		December 31, 2015
	($ in Thousands)
Commitments to extend credit, excluding commitments to originate residential mortgage loans held for sale(1)(2)	$	7,315,642	$	7,402,518
Commercial letters of credit(1)	7,782		9,945
Standby letters of credit(3)	278,740		296,508

1) These off-balance sheet financial instruments are exercisable at the market rate prevailing at the date the underlying transaction will be completed and, thus, are deemed to have no current fair value, or the fair value is based on fees currently charged to enter into similar agreements and is not material at March 31, 2016 or December 31, 2015.

2) Interest rate lock commitments to originate residential mortgage loans held for sale are considered derivative instruments and are disclosed in Note 10.

3) The Corporation has established a liability of $3 million at both March 31, 2016 and December 31, 2015, as an estimate of the fair value of these financial instruments.

Summary of changes in the residential mortgage repurchase reserve

The following summarizes the changes in the mortgage repurchase reserve.

	For the Three Months Ended March 31, 2016			For the Year Ended December 31, 2015
	($ in Thousands)
Balance at beginning of period	$	1,197		$	3,258
Repurchase provision expense	70			428
Adjustments to provision expense	—			(2,450		)
Charge offs, net	(3		)	(39		)
Balance at end of period	$	1,264		$	1,197