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The outstanding shares of the acquiree in a business acquisition.

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The fair value premium of the time deposits at the date of acquisition.

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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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Percentage of voting equity interests acquired at the acquisition date in the business combination.

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Price of a single share of a number of saleable stocks paid or offered to be paid in a business combination.

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of equity interests of the acquirer, including instruments or interests issued or issuable in consideration for the business combination.

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The amount of financial assets (as defined) recognized as of the acquisition date.

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Amount of intangible assets, excluding goodwill, acquired at the acquisition date.

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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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Useful life of finite-lived intangible assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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

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Any certificate of deposit or savings account held by a bank or other financial institution for a short-term specified period of time. Because of their short-term, time deposits are considered highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Basis of Presentation - Acquisitions (Details) - USD ($)	Oct. 01, 2018	Jan. 02, 2018	Aug. 15, 2017	Sep. 30, 2018	Dec. 31, 2017	Sep. 30, 2017
Acquisitions
Total assets				$ 3,806,949,000	$ 3,393,133,000	$ 3,237,485,000
Goodwill				5,302,000	3,902,000
Deposits				3,302,369,000	2,943,561,000
Loans Receivable, Net				1,905,859,000	1,366,349,000
Joy State Bank
Acquisitions
Total assets					$ 43,000,000
FM Bancorp
Acquisitions
Total assets				109,600,000
Deposits				95,700,000
Loans Receivable, Net				$ 35,000,000
RICHMAC
Acquisitions
Percentage of voting interests acquired			100.00%
Purchase price paid shares			$ 8,100,000
Goodwill			3,800,000
Intangible assets			$ 1,600,000
Joy State Bank \| Stock Purchase Agreement
Acquisitions
Total cost		$ 5,500,000
Goodwill		989,000
Intangible assets		478,000
Time deposits		16,700,000
Time deposits at fair value		16,900,000
Fair value premium of acquired time deposits		$ 185,000
Number of years of accretion against interest expense		20 months
Acquired loan portfolio		$ 27,900,000
Acquired loan portfolio at fair value		27,500,000
Fair value discount on acquired loan portfolio		$ 458,000
Number of years of accretion to interest income		39 months
Joy State Bank \| Core Deposits \| Stock Purchase Agreement
Acquisitions
Useful life		10 years
FM Bancorp, Inc
Acquisitions
Outstanding shares of the acquiree	27,537
Share price per share	$ 795.29
Total cost	$ 21,900,000