ACQUISITIONS - First Financial Bancorp. Merger (Details) $ / shares in Units, $ in Thousands	Jul. 25, 2017 USD ($) $ / shares	Apr. 28, 2017 USD ($)	Jun. 30, 2017 $ / shares	Feb. 13, 2017 item	Jan. 25, 2017 item	Dec. 31, 2016 $ / shares	Jun. 30, 2016 $ / shares	Dec. 31, 2015 $ / shares	Jun. 30, 2015 $ / shares
ACQUISITIONS
Share Price | $ / shares			$ 34.15			$ 19.89	$ 21.89	$ 19.89	$ 19.89
Columbus
ACQUISITIONS
No of branches divested | item					4
Greensburg
ACQUISITIONS
No of branches divested | item					1
German American Bancorp | Columbus
ACQUISITIONS
No of branches divested | item				4
German American Bancorp | Greensburg
ACQUISITIONS
No of branches divested | item				1
First Financial Bancorp
ACQUISITIONS
Ratio of shares to be received by acquiree shareholders	1.3875
Share Price | $ / shares	$ 28.10
Equity Instruments	$ 1,000,000
Assets	13,500,000
Loans	9,000,000
Deposits	10,400,000
Transaction costs	$ 10,000,000
FCB Bancorp, Inc.
ACQUISITIONS
Ratio of shares to be received by acquiree shareholders		0.9
Equity Instruments		$ 47,969
Acquisition of outstanding common shares (as a percent)		100.00%	100.00%
Loans		$ 427,541
FCB Bancorp, Inc. | First Financial Bancorp
ACQUISITIONS
Acquisition of outstanding common shares (as a percent)	37.00%