Condensed Consolidated Statements of Operations and Comprehensive Income (Unaudited) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2018	Mar. 31, 2017
Interest and Dividend Income
Loans receivable, including loan fees		$ 151,290	$ 124,910
Investment securities		6,458	4,406
Federal Home Loan Bank stock		396	412
Deposits with banks		1,556	1,076
Total interest and dividend income		159,700	130,804
Interest Expense
Time deposits		15,728	10,982
Other deposits		4,586	4,446
Securities sold under agreements to repurchase		714	1,550
Advances from Federal Home Loan Bank		971	288
Long-term debt		2,082	1,424
Deferred payments from acquisition		276
Total interest expense		24,357	18,690
Net interest income before reversal for credit losses		135,343	112,114
Reversal for credit losses		(3,000)	(2,500)
Net interest income after reversal for credit losses		138,343	114,614
Non-Interest Income
Net losses from equity securities		(3,847)
Securities gains/(losses), net			(466)
Letters of credit commissions		1,275	1,123
Depository service fees	[1]	6,867	6,660
Gain from acquisition		340
Other operating income		6,097	4,553
Total non-interest income		5,310	6,718
Non-Interest Expense
Salaries and employee benefits		30,377	25,871
Occupancy expense		5,452	4,699
Computer and equipment expense		3,094	2,724
Professional services expense		6,039	4,256
Data processing service expense		3,219	2,532
FDIC and regulatory assessments		2,035	2,520
Marketing expense		858	871
Other real estate owned (income)/expense		(212)	61
Amortization of investments in low income housing and alternative energy partnerships		5,761	4,850
Amortization of core deposit intangibles		234	172
Acquisition and integration costs		169
Other operating expense		3,945	3,330
Total non-interest expense		60,971	51,886
Income before income tax expense		82,682	69,446
Income tax expense		18,866	20,505
Net income		63,816	48,941
Other comprehensive income, net of tax
Unrealized holding losses on securities available-for-sale		(11,514)	(496)
Unrealized holding gain on cash flow hedge derivatives		2,193	299
Less: reclassification adjustments for gains/(losses) included in net income			(270)
Total other comprehensive gain, net of tax		(9,321)	73
Total other comprehensive income		$ 54,495	$ 49,014
Net income per common share:
Basic (in dollars per share)		$ 0.79	$ 0.61
Diluted (in dollars per share)		0.78	0.61
Cash dividends paid per common share (in dollars per share)		$ 0.24	$ 0.21
Weighted-average shares:
Basic (in shares)		81,123,380	79,703,593
Diluted weighted-average number of common shares outstanding (in shares)		81,680,445	80,413,178
Deposit Account [Member]
Non-Interest Income
Depository service fees		$ 1,445	$ 1,508

[1] There were no adjustments to the Company's financial statements recorded as a result of the adoption of ASC 606. For comparability, the Company has adjusted prior period amounts to conform to the periods presentation.