Commitments and Contingent Liabilities (Tables)

9 Months Ended

12 Months Ended

Sep. 30, 2016

Dec. 31, 2015

Commitments and Contingent Liabilities

Schedule of financial instruments with off-balance sheet risk

	September 30,		December 31,
(dollars in thousands)	2016		2015
Financial instruments whose contract amounts represent credit risk:
Commitments to extend credit	$	5,179,570	$	5,192,874
Standby letters of credit		105,742		127,840
Commercial letters of credit		9,315		8,404

	December 31,
(dollars in thousands)	2015		2014
Financial instruments whose contract amounts represent credit risk:
Commitments to extend credit	$	5,192,874	$	4,777,846
Standby letters of credit		127,840		53,943
Commercial letters of credit		8,404		10,067