Consolidated Statements of Income - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2018		Dec. 31, 2017		Dec. 31, 2016
Interest income:
Loans	$ 1,358,480		$ 1,025,788		$ 834,155
Investment securities:
Taxable	541,605		412,133		346,937
Non-taxable	34,616		5,714		2,234
Federal funds sold, securities purchased under agreements to resell and other short-term investment securities	35,208		21,505		10,070
Total interest income	1,969,909		1,465,140		1,193,396
Interest expense:
Deposits	29,306		8,676		5,611
Borrowings	46,615		36,095		37,262
Net interest income	75,921		44,771		42,873
Net interest income	1,893,988		1,420,369		1,150,523
Provision for credit losses	87,870		92,304		106,679	[1]
Net interest income after provision for loan losses	1,806,118		1,328,065		1,043,844
Noninterest income:
Gains on investment securities, net	88,094		64,603		51,740
Gains on equity warrant assets, net	89,142		54,555		37,892	[2]
Foreign exchange fees	138,812		115,760		104,183
Credit card fees	94,072		76,543		68,205
Deposit service charges	76,097		58,715		52,524
Client investment fees	130,360		56,136		32,219
Lending related fees	41,949		43,265		33,395
Letters of credit and standby letters of credit fees	34,600		28,544		25,644
Other	51,858		59,110		50,750	[2]
Noninterest income	744,984		557,231		456,552
Noninterest expense:
Compensation and benefits	726,980		606,402		514,270
Professional services	158,835		121,935		94,982
Premises and equipment	77,918		71,753		65,502
Net occupancy	54,753		48,397		39,928
Business development and travel	48,180		41,978		40,130
FDIC and state assessments	34,276		35,069		30,285
Correspondent bank fees	13,713		12,976		12,457
Other	73,538		72,145		62,243
Total noninterest expense	1,188,193		1,010,655		859,797	[1]
Income before income tax expense	1,362,909		874,641		640,599
Income tax expense	351,561	[3]	355,463	[3]	250,333
Net income before noncontrolling interests	1,011,348		519,178		390,266
Net income attributable to noncontrolling interests	(37,508)		(28,672)		(7,581)
Net income available to common stockholders	$ 973,840	[3]	$ 490,506	[3]	$ 382,685
Earnings per common share—basic (usd per share)	$ 18.35	[3]	$ 9.33	[3]	$ 7.37
Earnings per common share—diluted (usd per share)	$ 18.11	[3]	$ 9.20	[3]	$ 7.31

[1] Our consolidated statements of income for the year ended December 31, 2016 was modified from prior periods’ presentation to conform to the current period's presentation, which reflects our provision for loan losses and provision for unfunded credit commitments together as our “provision for credit losses”. In prior periods, our provision for unfunded credit commitments were reported separately as a component of noninterest expense.

[2] Our consolidated statements of income for the year ended December 31, 2016 was modified from prior periods’ presentation to conform to the current period's presentation, which reflects a new line item to separately disclose net gains on equity warrant assets. In prior periods, net gains on equity warrant assets were reported as a component of net gains on derivative instruments. We removed the line item "gains on derivative instruments, net" and reclassified all other gains on derivative instruments, net to other noninterest income.

[3] Included in income tax expense, net income available to common stockholders, earnings per common share-basic and earnings for common share-diluted, for the years ended December 31, 2018 and 2017, are tax benefits recognized associated with the adoption of Accounting Standards Update ("ASU") 2016-09, Improvements to Employee Share-Based Payment Accounting in the first quarter of 2017. This guidance was adopted on a prospective basis with no change to prior period amounts.