SHAREHOLDERS' EQUITY (Details)	3 Months Ended
	Mar. 31, 2017 USD ($) series fund Vote shares	Mar. 31, 2016 USD ($) shares	Dec. 31, 2016 shares
Shareholders' equity
Preferred stock, shares authorized	50,000,000		50,000,000
Preferred stock, shares outstanding	0		0
Number of votes for a share of common stock | Vote	1
Number of sinking fund provisions applicable to common stock | fund	0
Common stock, shares issued	90,965,482		90,952,185
Total Number of Shares Purchased or Withheld
Shares repurchased or withheld from restricted stock awards	2,574	2,588
Maximum
Shareholders' equity
Preferred stock, shares authorized	50,000,000
Minimum
Shareholders' equity
Number of series of preferred stock that may be issued | series	1
Treasury Stock
Total Number of Shares Purchased or Withheld
Aggregate purchase price of shares repurchased or withheld from restricted stock awards | $	$ 7,475	$ 8,933