Commitments, Off-Balance Sheet Arrangements, and Legal Proceedings (Details Textuals) $ in Thousands	Jan. 11, 2016 USD ($) complaint	May 22, 2015 USD ($) loan_production_office branch	Mar. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
unfunded commitments			$ 24,000	$ 25,000
Carrying value of investments			111,000	85,000
Commitments under unconsolidated projects			80,000	69,000
Commitment term		3 years
Mortgage loan commitment		$ 196,000
Number of branch opening commitments | branch		1
Number of loan production offices | loan_production_office		4
Conciliation agreement cost, commitment term		4 years
Number of complaints filed under legal proceedings | complaint	2
Loans repurchased under make whole requests			112	2,000
Loans sold to outside investors original amount			9,400,000
Loans sold to outside investors remaining outstanding amount			6,100,000
Residential mortgage loans sold with recourse risk			45,000	62,000
Residential mortgage loans sold with credit recourse risk			$ 92,000	$ 98,000
The Official Committee of Unsecured Creditors of World Marketing Chicago LLC v Associated Bank [Member]
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Damages sought	$ 6,000
Damages sought, cash	4,000
American Funds Service Company v Associated Bank [Member]
Commitments, Off-Balance Sheet Arrangements, and Contingent Liabilities (Textuals) [Line Items]
Damages sought	$ 600