STOCK-BASED COMPENSATION (Details) (USD $) In Thousands, except Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2014 item	Dec. 31, 2013 item	Dec. 31, 2012	Dec. 31, 2011
Performance awards
Stock-based compensation
Performance shares award issued	203,295	298,500
PLC
No. of SARs
Number of shares of common stock that may be issued under plans approved by shareowners	9,500,000
PLC | Performance awards
Stock-based compensation
Period over which ROE is calculated	3 years	3 years
Minimum percentage of the company's ROE to earn awards under 2014 performance awards	10.50%	10.00%
Number of awards earned when ROE is below specified floor percentage	0	0
Minimum percentage of Company's ROE to earn maximum awards under 2014 performance awards	12.00%	11.50%
Performance shares award issued	203,295	298,500	306,100	191,100
Estimated fair value of performance shares issued	$ 10,484	$ 9,328	$ 8,608	$ 5,433
PLC | SARs
Stock-based compensation
Performance shares award issued	0	0	0
Expiration period from date of grant	10 years
Exercisable period of grants from grant date	5 years
Beginning of annual installments from date of grant	1 year
Weighted-Average Base Price per share
Balance at the beginning of the period (in dollars per share)	$ 23.08	$ 22.15	$ 22.27
SARs exercised / forfeited (in dollars per share)	$ 22.07	$ 18.54	$ 22.60
Balance at the end of the period (in dollars per share)	$ 30.41	$ 23.08	$ 22.15
No. of SARs
Balance at the beginning of the period (in shares)	1,305,101	1,641,167	2,274,229
SARs exercised / forfeited (in shares)	(1,147,473)	(336,066)	(633,062)
Balance at the end of the period (in shares)	157,628	1,305,101	1,641,167
PLC | SARs | Minimum
Stock-based compensation
Number of annual installments to exercise stock appreciation rights	3
PLC | SARs | Maximum
Stock-based compensation
Number of annual installments to exercise stock appreciation rights	4