SHARE-BASED COMPENSATION (Tables)

3 Months Ended

Mar. 31, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Transactions Involving Stock Units and Director Stock Grants

Transactions involving our stock units and director stock grants during the three months ended March 31, 2018 are summarized below:

	Three Months Ended March 31, 2018
	(unaudited)
	No. of Stock Units		Weighted Average Fair Value
	(in thousands)
Stock and stock units, beginning of period	854		$	21.42
Changes during the period:
Granted	5		$	16.68
Vested and settled	(33	)	$	20.05
Cancelled	(2	)	$	21.26
Stock and stock units, end of period	824		$	21.38

Summary of Transactions Involving Performance Awards

Transactions involving our performance awards during the three months ended March 31, 2018 are summarized below:

	Three Months Ended March 31, 2018
	(unaudited)
	Performance Units Subject to Market Conditions			Performance Units Not Subject to Market Conditions
	No. of Stock Units1	Weighted Average Fair Value		No. of Stock Units1		Weighted Average Fair Value
	(in thousands)			(in thousands)
Performance stock units, beginning of period	45	$	17.66	84		$	25.76
Changes during the period:
Granted	453	$	13.94	103		$	14.15
Vested and settled	—	$	—	(15	)	$	13.45
Cancelled	—	$	—	—		$	—
Performance stock units, end of period	498	$	14.26	172		$	19.89

_________________

1 Performance units with variable payouts are shown at target level of performance.

Summary of Transactions Involving Stock Options

Transactions involving our stock options during the three months ended March 31, 2018 are summarized below:

	Three Months Ended March 31, 2018
	(unaudited)
	No. of Options		Weighted Average Exercise Price
	(in thousands)
Shares under option, beginning of period	79		$	31.94
Changes during the period:
Granted	—		$	—
Exercised	—		$	—
Cancelled	—		$	—
Expired	(2	)	$	34.19
Shares under option, end of period	77		$	31.88
Exercisable at end of period	77		$	31.88