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Recent Accounting Pronouncements (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2017
Recent Accounting Pronouncements [Abstract]
Federal corporate tax rate			21.00%		35.00%
Salaries and employee benefits	$ 37,726	$ 33,503	$ 74,293	$ 67,736
Other noninterest expense	$ 4,332	4,868	$ 8,747	9,397
ASU 2018-02 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation					$ 0
ASU 2017-07 [Member]
Recent Accounting Pronouncements [Abstract]
Salaries and employee benefits		400		800
Other noninterest expense		$ (400)		$ (800)
AOCI [Member] | ASU 2016-01 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation					(2,600)
Retained Earnings [Member] | ASU 2016-01 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation					2,600
AOCI [Member] | ASU 2018-02 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation					(5,575)
Retained Earnings [Member] | ASU 2018-02 [Member]
Recent Accounting Pronouncements [Abstract]
Reclassification upon ASU implementation					$ 5,575

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