Sum of the carrying amounts as of the balance sheet date of all assets that are recognized. Assets are probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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The aggregate of all deposit liabilities held by the entity, including foreign and domestic, interest and noninterest bearing; may include demand deposits, saving deposits, Negotiable Order of Withdrawal (NOW) and time deposits among others.

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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Describes the event or transaction that occurred between the balance sheet date and the date the financial statements are issued or available to be issued.

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Subsequent Event Subsequent Event (Details Textual) - USD ($)	Oct. 26, 2017	Sep. 30, 2017	Dec. 31, 2016
Subsequent Event
Total assets		$ 9,798,602,000	$ 9,450,600,000
Gross loans		$ 6,509,433,000	$ 5,684,463,000
First Security Bank
Subsequent Event
Subsequent Event, Description	the Company announced the signing of a definitive agreement to acquire Inter-Mountain Bancorp, Inc. and its wholly-owned subsidiary, First Security Bank, a community bank based in Bozeman, Montana
Total assets	$ 1,009,623,000
Gross loans	657,626,000
Total deposits	$ 873,572,000