PARENT COMPANY ONLY FINANCIAL STATEMENTS - Condensed Statements of Income (Details) - USD ($)
$ in Thousands
 3 Months Ended 12 Months Ended
Dec. 31, 2016
Sep. 30, 2016
Jun. 30, 2016
Mar. 31, 2016
Dec. 31, 2015
Sep. 30, 2015
Jun. 30, 2015
Mar. 31, 2015
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
OPERATING EXPENSE:                      
Interest expense on borrowed funds                 $ 10,914 $ 8,640 $ 5,571
INCOME TAX BENEFIT                 (9,554) (7,775) (4,828)
INCOME BEFORE INCOME TAXES                 32,405 23,561 13,833
NET INCOME                 22,851 15,786 9,005
Preferred stock dividends                 0 559 0
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS $ 5,771 $ 5,471 $ 5,254 $ 6,355 $ 4,212 $ 4,047 $ 3,623 $ 3,345 22,851 15,227 9,005
Parent Company                      
OPERATING INCOME:                      
Other income                 11 16 0
Total income                 11 16 0
OPERATING EXPENSE:                      
Interest expense on borrowed funds                 30 707 229
Other expenses                 1,204 771 810
Total operating expense                 1,234 1,478 1,039
INCOME BEFORE INCOME TAX BENEFIT AND EQUITY IN UNDISTRIBUTED EARNINGS OF SUBSIDIARIES                 (1,223) (1,462) (1,039)
INCOME TAX BENEFIT                 428 500 353
INCOME BEFORE INCOME TAXES                 (795) (962) (686)
EQUITY IN UNDISTRIBUTED EARNINGS OF SUBSIDIARIES                 23,646 16,748 9,691
NET INCOME                 22,851 15,786 9,005
Preferred stock dividends                 0 559 0
NET INCOME ATTRIBUTABLE TO COMMON STOCKHOLDERS                 $ 22,851 $ 15,227 $ 9,005