Subsequent Event	9 Months Ended
Sep. 30, 2021
Subsequent Events [Abstract]
Subsequent Event	Subsequent EventOn November 2, 2021, the Company announced it has entered into a definitive agreement to acquire First Century Bancorp. (“First Century”), the parent company of First Century Bank, N.A., headquartered in Roswell, GA. According to the terms of the definitive agreement, First Internet will acquire all of the outstanding shares of First Century common stock for $80 million in cash, which First Internet will fund with available on-balance sheet cash. As of September 30, 2021, First Century had total assets of $408 million, total deposits of $330 million, and total loans of $32 million. The transaction, which remains subject to regulatory approvals, is expected to close in the first quarter 2022.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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