Business and Summary of Significant Accounting Policies (Details)	3 Months Ended										9 Months Ended	12 Months Ended
	Dec. 31, 2016 USD ($) branch office atm	Sep. 30, 2016 USD ($)	Jun. 30, 2016 USD ($)	Mar. 31, 2016 USD ($)	[1]	Dec. 31, 2015 USD ($)		Sep. 30, 2015 USD ($)	Jun. 30, 2015 USD ($)	Mar. 31, 2015 USD ($)	Sep. 30, 2016	Dec. 31, 2016 USD ($) reporting_unit_level branch office atm $ / shares	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Accounting Policy [Line Items]
Cash	$ 50,300,000					$ 42,900,000						$ 50,300,000	$ 42,900,000
Net Income (Loss) Attributable to Parent	10,902,000	$ 10,903,000	$ 9,616,000	$ 8,646,000		1,692,000	[2]	$ 6,456,000	$ 7,193,000	$ 5,611,000		40,067,000	20,952,000	$ 24,570,000
Trading Securities	0					0						0	0
Cash and Cash Equivalents, at Carrying Value	$ 87,707,000					79,488,000						$ 87,707,000	79,488,000	60,813,000	$ 51,355,000
Number of Branches | branch	61											61
Number of ATMs | atm	84											84
Number of commercial production offices | office	2											2
Equity Method Investment, Ownership Percentage	100.00%											100.00%
Loans Held-for-sale	$ 14,836,000					10,958,000						$ 14,836,000	10,958,000
Financing Receivable, Individually Evaluated for Impairment	20,254,000					15,235,000						$ 20,254,000	15,235,000	12,924,000
Number of Reporting Unit Levels | reporting_unit_level												2
Goodwill impairment												$ 0	0	0
BOLI single carrier percentage of Tier I capital												15.00%
BOLI CSV percentage of Tier I Capital												25.00%
Interest-bearing Deposits in Banks and Other Financial Institutions	37,400,000					36,600,000						$ 37,400,000	36,600,000
HTM securities	94,609,000					84,144,000						94,609,000	84,144,000
AFS securities	779,867,000					750,338,000						779,867,000	750,338,000
Available-for-sale Securities, Amortized Cost Basis	789,229,000					756,186,000						$ 789,229,000	756,186,000
Stockholders' Equity Note, Stock Split, Conversion Ratio											1.5	1.5
Minimum [Member]
Accounting Policy [Line Items]
Financing Receivable, Individually Evaluated for Impairment	250,000											$ 250,000
Finite-lived intangible asset, useful life (years)												5 years
Maximum [Member]
Accounting Policy [Line Items]
Finite-lived intangible asset, useful life (years)												10 years
Residential Portfolio Segment [Member]
Accounting Policy [Line Items]
Term to maturity (years)												30 years
Financing Receivable, Individually Evaluated for Impairment	4,348,000					6,026,000						$ 4,348,000	6,026,000	6,411,000
Restatement Adjustment [Member]
Accounting Policy [Line Items]
Net Income (Loss) Attributable to Parent												$ 697,000
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Basic Earnings Per Share | $ / shares												$ 0.05
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Diluted Earnings Per Share | $ / shares												$ 0.04
Retained Earnings [Member]
Accounting Policy [Line Items]
Net Income (Loss) Attributable to Parent												$ 40,067,000	20,952,000	$ 24,570,000
New Accounting Pronouncement or Change in Accounting Principle, Effect of Change on Net Income												(72,000)
Equity Securities [Member]
Accounting Policy [Line Items]
AFS securities	741,000					705,000						741,000	705,000
Available-for-sale Securities, Amortized Cost Basis	632,000					$ 712,000						632,000	$ 712,000
Substandard | Minimum [Member]
Accounting Policy [Line Items]
Financing Receivable, Individually Evaluated for Impairment	$ 500,000											$ 500,000

[1] (1)In the second quarter of 2016, the Company adopted ASU 2016-09 effective as of January 1, 2016. As such, first quarter 2016 financial results have been restated from previously reported within Form 10-Q.

[2] On October 16, 2015, the Company completed its acquisition of SBM. Fourth quarter 2015 results of operations include revenues and expenses incurred as a combined organization from the acquisition date through December 31, 2015. The decrease in basic and diluted EPS in the fourth quarter of 2015 was due to acquisition costs and the issuance of 4.1 million shares of Company common stock (as adjusted for the three-for-two common stock split effective September 30, 2016) in connection with the acquisition. Refer to Note 2 for additional details of the acquisition