Consolidated Statements of Stockholders' Equity (Parenthetical)	3 Months Ended	9 Months Ended
Dec. 31, 2017 $ / shares shares	Sep. 30, 2018 $ / shares shares	Sep. 30, 2017 $ / shares shares
Stock issued for employee stock purchase plan, shares (in shares)		39,782	26,002
Stock issued for compensation plans, shares (in shares)	116,190	226,715	243,096
Cash dividends per share (in dollars per share) \| $ / shares	$ 0.125	$ 0.45	$ 0.375
Hardeman County Investment Company, Inc.
Stock issued for acquisition (in shares)			1,599,940
OKSB Merger
Stock issued for acquisition (in shares)	14,488,604
First Texas Merger
Stock issued for acquisition (in shares)	12,999,840

Aggregate dividends declared during the period for each share of common stock outstanding.

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