Loans and the Allowance for Loan Losses (Details) - Credit quality indicators - USD ($) $ in Thousands	Dec. 31, 2019	Dec. 31, 2018
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	$ 5,118,294	$ 4,544,899
Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	4,998,910	4,456,187
Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	37,069	21,460
Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	82,315	67,252
Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount
Commercial Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,129,661	988,758
Commercial Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	1,059,852	951,610
Commercial Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	22,159	3,371
Commercial Portfolio Segment [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	47,650	33,777
Commercial Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount
Commercial Real Estate Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,041,959	2,778,167
Commercial Real Estate Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,014,956	2,742,989
Commercial Real Estate Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	10,301	12,574
Commercial Real Estate Portfolio Segment [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	16,702	22,604
Commercial Real Estate Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount
Commercial construction [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	623,326	465,389
Commercial construction [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	604,298	453,598
Commercial construction [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	4,609	5,515
Commercial construction [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	14,419	6,276
Commercial construction [Member] | Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount
Residential Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	320,020	309,991
Residential Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	316,476	305,414
Residential Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount
Residential Portfolio Segment [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,544	4,577
Residential Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount
Consumer Portfolio Segment [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,328	2,594
Consumer Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount	3,328	2,576
Consumer Portfolio Segment [Member] | Special Mention [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount
Consumer Portfolio Segment [Member] | Substandard [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount		18
Consumer Portfolio Segment [Member] | Doubtful [Member]
Financing Receivable, Credit Quality Indicator [Line Items]
Loans and Leases Receivable, Gross, Carrying Amount