Goodwill	12 Months Ended
Dec. 31, 2014
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill	GOODWILL Goodwill was $180.1 million at December 31, 2014 and $120.2 million at December 31, 2013. During 2014, the Corporation acquired Northwestern, which resulted in the recognition of $60.0 million of goodwill. Goodwill recognized in the Northwestern transaction was primarily attributable to the synergies and economies of scale expected from combining the operations of the Corporation and Northwestern. None of the goodwill recorded in conjunction with the Northwestern acquisition is deductible for tax purposes. During 2012, the Corporation acquired 21 branches from Independent Bank, which resulted in the recognition of $6.8 million of goodwill, with $5.9 million deductible for tax purposes. Goodwill recognized in the branch acquisition transaction was primarily attributable to the premium paid by the Corporation to acquire customer core deposit accounts, which are primarily located in markets where the Corporation previously did not operate. Goodwill is subject to impairment testing annually and on an interim basis if events or changes in circumstances indicate assets might be impaired. The Corporation's most recent goodwill impairment test performed as of October 31, 2014 did not indicate that an impairment of goodwill existed. The Corporation also determined that no triggering events occurred that indicated impairment from the most recent valuation date through December 31, 2014 and that the Corporation's goodwill was not impaired at December 31, 2014.

GOODWILL

Goodwill was $180.1 million at December 31, 2014 and $120.2 million at December 31, 2013. During 2014, the Corporation acquired Northwestern, which resulted in the recognition of $60.0 million of goodwill. Goodwill recognized in the Northwestern transaction was primarily attributable to the synergies and economies of scale expected from combining the operations of the Corporation and Northwestern. None of the goodwill recorded in conjunction with the Northwestern acquisition is deductible for tax purposes. During 2012, the Corporation acquired 21 branches from Independent Bank, which resulted in the recognition of $6.8 million of goodwill, with $5.9 million deductible for tax purposes. Goodwill recognized in the branch acquisition transaction was primarily attributable to the premium paid by the Corporation to acquire customer core deposit accounts, which are primarily located in markets where the Corporation previously did not operate.

Goodwill is subject to impairment testing annually and on an interim basis if events or changes in circumstances indicate assets might be impaired. The Corporation's most recent goodwill impairment test performed as of October 31, 2014 did not indicate that an impairment of goodwill existed. The Corporation also determined that no triggering events occurred that indicated impairment from the most recent valuation date through December 31, 2014 and that the Corporation's goodwill was not impaired at December 31, 2014.