Loans and Allowance for Loan Losses (Credit Risk Exposure Indicators by Portfolio Segment) (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 2,594,564	$ 2,490,206	$ 1,772,610
Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	2,173,031	2,023,263
Performing Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Loans	345,615	364,536
Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	13,966	34,720
Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	58,872	65,636
Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,456
Nonperforming Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Loans	1,624	2,051
Residential real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans	802,494	820,617	585,468
Residential real estate loans | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	789,554	802,873
Residential real estate loans | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	2,387	3,282
Residential real estate loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	10,553	14,462
Commercial real estate loans
Financing Receivable, Recorded Investment [Line Items]
Loans	1,050,780	927,951	640,661
Commercial real estate loans | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,003,386	868,664
Commercial real estate loans | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	5,724	20,732
Commercial real estate loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	41,670	38,555
Commercial loans
Financing Receivable, Recorded Investment [Line Items]
Loans	333,639	297,721	257,515
Commercial loans | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	321,148	281,553
Commercial loans | Special Mention [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	5,598	7,527
Commercial loans | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	5,437	8,641
Commercial loans | Doubtful [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	1,456
Home equity loans
Financing Receivable, Recorded Investment [Line Items]
Loans	329,907	348,634	271,709
Home equity loans | Performing Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Loans	328,287	346,701
Home equity loans | Nonperforming Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Loans	1,620	1,933
Consumer loans
Financing Receivable, Recorded Investment [Line Items]
Loans	17,332	17,953	$ 17,257
Consumer loans | Performing Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Loans	17,328	17,835
Consumer loans | Nonperforming Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Loans	4	118
HPFC Portfolio Segment [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	60,412	77,330
HPFC Portfolio Segment [Member] | Pass [Member]
Financing Receivable, Recorded Investment [Line Items]
Loans	77,330
HPFC Portfolio Segment [Member] | Performing Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Loans	58,943	70,173
HPFC Portfolio Segment [Member] | Substandard
Financing Receivable, Recorded Investment [Line Items]
Loans	257	3,179
HPFC Portfolio Segment [Member] | Nonperforming Financing Receivable
Financing Receivable, Recorded Investment [Line Items]
Loans	$ 1,212	$ 3,978