Quarterly Financial Data (Unaudited) (Tables)

12 Months Ended

Dec. 31, 2015

Quarterly Financial Information Disclosure [Abstract]

Summary of quarterly financial data

Summarized quarterly financial data are as follows:

	First Quarter		Second Quarter		Third Quarter		Fourth Quarter
	(in millions, except per unit amounts)
2015
Net sales	$	126.6	$	153.6	$	150.2	$	151.3
Gross margin	65.0		103.7		74.1		83.0
Net earnings	59.0		99.3		69.4		79.2
Net earnings per Common Unit	2.03		3.31		2.23		2.49
2014
Net sales	$	177.7	$	167.5	$	135.1	$	168.0
Gross margin	107.5		104.2		76.1		98.9
Net earnings	102.9		100.1		72.0		95.0
Net earnings per Common Unit	3.26		3.16		2.60		3.05