Acquisitions (Acquisitions Fair Values) (Details) - USD ($) $ in Thousands	Feb. 05, 2016	Nov. 30, 2015	Jan. 16, 2015	Dec. 31, 2016	Dec. 31, 2015
Fair value of liabilities assumed
Goodwill resulting from acquisition				$ 127,699	$ 97,852
CIC Bancshares, Inc.
Fair value of consideration paid
Common stock (in shares)	2,003,235
Cash	$ 15,672
Total consideration paid	76,882
Fair value of assets acquired
Cash and due from banks	23,756
Securities:
Securities available for sale	92,831
Other securities	3,486
Loans held to maturity	581,477
Premises, furniture and equipment, net	16,450
Other real estate, net	1,934
Core deposit intangibles and customer relationship intangibles, net	6,576
Other assets	16,276
Total assets	742,786
Fair value of liabilities assumed
Deposits	648,111
Short term borrowings	35,766
Other borrowings	7,924
Other liabilities	3,951
Total liabilities assumed	695,752
Fair value of net assets acquired	47,034
Goodwill resulting from acquisition	$ 29,848
Premier Valley Bank
Fair value of consideration paid
Common stock (in shares)		1,758,543
Cash		$ 28,522
Total consideration paid		95,540
Fair value of assets acquired
Cash and due from banks		77,127
Securities:
Securities available for sale		181,647
Securities held to maturity		0
Other securities		4,554
Loans held for sale		0
Loans held to maturity		389,787
Premises, furniture and equipment, net		4,221
Other real estate, net		0
Core deposit intangibles and customer relationship intangibles, net		8,596
Other assets		26,790
Total assets		692,722
Fair value of liabilities assumed
Deposits		622,676
Short term borrowings		0
Other borrowings		0
Other liabilities		15,530
Total liabilities assumed		638,206
Fair value of net assets acquired		54,516
Goodwill resulting from acquisition		$ 41,024
Community Banc-Corp of Sheboygan, Inc.
Fair value of consideration paid
Common stock (in shares)			1,970,720
Cash			$ 6
Total consideration paid			53,058
Fair value of assets acquired
Cash and due from banks			7,109
Securities:
Securities available for sale			52,976
Other securities			1,284
Loans held for sale			728
Loans held to maturity			395,007
Premises, furniture and equipment, net			13,954
Other real estate, net			346
Core deposit intangibles and customer relationship intangibles, net			10,295
Other assets			25,066
Total assets			506,765
Fair value of liabilities assumed
Deposits			433,919
Short term borrowings			24,836
Other borrowings			6,097
Other liabilities			7,434
Total liabilities assumed			472,286
Fair value of net assets acquired			34,479
Goodwill resulting from acquisition			$ 18,579
Common Stock | CIC Bancshares, Inc.
Fair value of consideration paid
Common stock (in shares)	2,003,235
Common stock	$ 57,433
Common Stock | Premier Valley Bank
Fair value of consideration paid
Common stock (in shares)		1,758,543
Common stock		$ 67,018
Common Stock | Community Banc-Corp of Sheboygan, Inc.
Fair value of consideration paid
Common stock (in shares)			1,970,720
Common stock			$ 53,052
Preferred Stock | CIC Bancshares, Inc.
Fair value of consideration paid
Common stock (in shares)	3,000
Common stock	$ 3,777