Acquisition (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2017 USD ($) shares	Apr. 03, 2017 USD ($) branch
Business Acquisition [Line Items]
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Marketable Securities		$ 88,986
Branch Acquisition, Number of Branches | branch		9
Business Combination, Separately Recognized Transactions, Additional Disclosures, Acquisition Cost Expensed	$ 10,200
Branch Acquisition, Number of Limited Service Branches | branch		4
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Federal Home Loan Bank Stock		$ 3,250
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Receivables		383,083
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Property, Plant, and Equipment		12,113
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Intangible Assets, Other than Goodwill		5,998
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Other Real Estate Owned		68
Business Combination, Recognized Identifiable Assets Acquired And Liabilities Assumed, Bank Owned Life Insurance		20,522
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Assets, Prepaid Expense and Other Assets		16,305
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Assets		554,745
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Deposits		484,366
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Capital Lease Obligation		7,851
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Current Liabilities, Other		1,182
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Liabilities		493,399
Business Combination, Recognized Identifiable Assets Acquired, Goodwill, and Liabilities Assumed, Net		61,346
Cash paid to shareholders	$ 21,232
Business Combination, Consideration Transferred, Equity Interests Issued and Issuable Fair Value Method	110812
Business Acquisition, Equity Interest Issued or Issuable, Number of Shares | shares	8,356,882
Business Combination, Recognized Identifiable Assets Acquired and Liabilities Assumed, Cash and Equivalents		24,420
Shares issued to shareholders (8,356,882 shares)	$ 132,044
Business Combination, Goodwill Recognized, Description	70698
Business Combination, Acquired Receivables, Gross Contractual Amount		390,760
Business Combination, Acquired Receivables, Fair Value Adjustment		$ (7,700)