SHAREHOLDER'S EQUITY (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended		12 Months Ended
	Aug. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Dividends And Shares Activitiy [Line Items]
Dvidend Equivalent liability - short term		$ 446		$ 446			$ 260
Dvidend Equivalent liability - long term		637		637			348
Total Dividend Equivalent Liability		1,083		1,083			608
Dividend payments		$ 2,900		16,550	$ 5,772
Amount recorded as financing activity				(2,546)	(2,205)		(2,268)
Dividends paid on preferred stock				$ 1,650			1,788
Employee stock purchase plan, authorized shares		1,000		1,000
Stock Issued During Period Value Employee Stock Purchase Plan				$ 182			$ 379
Total Non cash compensation expense recognized		$ 1,032	$ 754	$ 3,101	3,023			$ 2,594
Espp Shares Market Value		85.00%		85.00%
Espp Share Discount		15.00%		15.00%
Dividends Paid on Common Stock - Special Dividend				$ 7,800
PaymentsOfDividendsAbstract
Payments of Dividends, Common Stock		$ 2,900		16,550	5,772
PaymentsOfDividendsPreferredStockAndPreferenceStock				1,650	$ 1,238
Share Repurchase Program
Treasury Stock Line Items
Stock Repurchase Prgram Authorized Amount		$ 100,000		100,000
Equity impact of cost of treasury stock purchased during period - Cost				$ 30,000
Dividends
Dividends And Shares Activitiy [Line Items]
CommonStockDividendsPerShareDeclared	$ 0.2			$ 0.09		$ 0.3
Dividend payments				$ 12,100
Dividend Payments No Pro Forma Effect				3,000
PaymentsOfDividendsAbstract
Payments of Dividends, Common Stock				$ 12,100
ESPP [Member]
Dividends And Shares Activitiy [Line Items]
Stock Issued During Period Shares Employee Stock Purchase Plans				15	18			0
Total Non cash compensation expense recognized				$ 32	$ 34			$ 0