Note 2 - RSU Summary (Details)	3 Months Ended
	Mar. 31, 2016 $ / shares shares
Time-Based RSUs [Member]
Shares (in shares) | shares	499,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 40.75
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares	61,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 58.98
Shares (in shares) | shares	(71,000)
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 35.11
Shares (in shares) | shares	(14,000)
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 43.08
Shares (in shares) | shares	475,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 43.87
PSUs and MPSUs [Member]
Shares (in shares) | shares	1,933,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 38.99
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares	1,013,000	[1]
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 39.50
Shares (in shares) | shares	(97,000)	[2]
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 42.77
Shares (in shares) | shares	(421,000)
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 29.92
Shares (in shares) | shares	(125,000)
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 36.84
Shares (in shares) | shares	2,303,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 40.83
MSUs [Member]
Shares (in shares) | shares	1,800,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 23.57
Shares (in shares) | shares	(180,000)
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 23.57
Shares (in shares) | shares	1,620,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 23.57
Shares (in shares) | shares	4,232,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 32.64
Share-based Compensation Arrangement by Share-based Payment Award, Equity Instruments Other than Options, Grants in Period | shares	1,074,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 40.61
Shares (in shares) | shares	(97,000)
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 42.77
Shares (in shares) | shares	(492,000)
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 30.66
Shares (in shares) | shares	(319,000)
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 29.63
Shares (in shares) | shares	4,398,000
Weighted-Average Grant Date Fair Value Per Share (in dollars per share) | $ / shares	$ 34.80

[1] Amount reflects the maximum number of PSUs and MPSUs that can be earned assuming the achievement of the highest level of performance conditions

[2] Amount reflects the number of PSUs and MPSUs that have not been earned or may not be earned based on management’s probability assessment at each reporting period.