Loans and Allowance for Credit Losses (Details 3) - USD ($) $ in Thousands	Jun. 30, 2017	Dec. 31, 2016	Jun. 30, 2016
Loans and leases receivable, net of deferred income	$ 5,985,031	$ 5,677,893	$ 5,403,429
Residential Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	151,115	152,748	150,129
Owner Occupied Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	660,066	640,870	584,358
Other Consumer Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	2,734	10,365	8,470
Income Producing Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	2,596,230	2,509,517	2,461,581
Home Equity Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	103,671	105,096	110,697
Construction Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	1,151,479	1,058,569	947,331
Commercial Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	1,319,736	1,200,728	1,140,863
Pass [Member]
Loans and leases receivable, net of deferred income	5,878,515	5,597,416	5,313,636
Pass [Member] | Residential Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	150,449	151,831	149,181
Pass [Member] | Owner Occupied Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	642,342	630,827	572,598
Pass [Member] | Other Consumer Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	2,639	10,237	8,467
Pass [Member] | Income Producing Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	2,564,780	2,489,407	2,424,180
Pass [Member] | Home Equity Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	101,963	103,484	108,954
Pass [Member] | Construction Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	1,139,629	1,051,445	938,148
Pass [Member] | Commercial Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	1,276,713	1,160,185	1,112,108
Watch and Special Mention [Member]
Loans and leases receivable, net of deferred income	70,163	46,006	57,193
Watch and Special Mention [Member] | Residential Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	666	676	694
Watch and Special Mention [Member] | Owner Occupied Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	12,354	7,950	10,499
Watch and Special Mention [Member] | Other Consumer Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	2	2	3
Watch and Special Mention [Member] | Income Producing Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	19,111	5,053	22,763
Watch and Special Mention [Member] | Home Equity Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	1,114	1,612	1,622
Watch and Special Mention [Member] | Construction Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	2,822	607	3,770
Watch and Special Mention [Member] | Commercial Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	34,094	30,106	17,842
Substandard [Member]
Loans and leases receivable, net of deferred income	36,353	34,471	32,600
Substandard [Member] | Residential Portfolio Segment [Member]
Loans and leases receivable, net of deferred income		241	254
Substandard [Member] | Owner Occupied Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	5,370	2,093	1,261
Substandard [Member] | Other Consumer Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	93	126
Substandard [Member] | Income Producing Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	12,339	15,057	14,638
Substandard [Member] | Home Equity Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	594		121
Substandard [Member] | Construction Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	9,028	6,517	5,413
Substandard [Member] | Commercial Portfolio Segment [Member]
Loans and leases receivable, net of deferred income	8,929	$ 10,437	$ 10,913
Doubtful [Member] | Commercial Portfolio Segment [Member]
Loans and leases receivable, net of deferred income