Related Party Transactions (Details) - USD ($)		12 Months Ended
	Apr. 03, 2018	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Equity Method Investments and Joint Ventures [Abstract]
Equity method investment, ownership interest		50.00%
Investment in unconsolidated affiliate		$ 156,100,000	$ 125,900,000
Equity in earnings of unconsolidated affiliates		31,800,000	25,900,000	$ 29,800,000
ART's assets, liabilities and results of operations:
Current assets		307,400,000	239,800,000
Noncurrent assets		160,200,000	91,500,000
Total assets		467,600,000	331,300,000
Current liabilities		133,300,000	82,400,000
Noncurrent liabilities		25,300,000	300,000
Total liabilities		158,600,000	82,700,000
Net sales		487,500,000	447,300,000	388,900,000
Costs and expenses applicable to net sales		410,600,000	379,800,000	322,100,000
Income before income taxes		65,500,000	53,600,000	60,800,000
Net income		64,200,000	52,100,000	59,300,000
Related party transactions:
Product manufactured for ART		229,100,000	213,800,000	210,400,000
Related Party Transaction, markup of product manufactured for ART reducing COGS		4,500,000	4,200,000	4,200,000
Charges for fixed costs, research and development and selling, general and administrative services to ART		$ 41,800,000	41,700,000	$ 33,800,000
Schedule of Investments [Line Items]
Debt Instrument, Frequency of Periodic Payment		monthly
Debt Instrument, Maturity Date Range, End		8 years
Noncurrent liability		$ 98,800,000	32,700,000
Grace LOC to ART [Member]
Schedule of Investments [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 15,000,000
Commitment fee on credit facility		0.10%
Long-term Line of Credit		$ 0	0
Chevron LOC to ART [Member]
Schedule of Investments [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity		$ 15,000,000.0
Commitment fee on credit facility		0.10%
Joint Venture [Member]
Schedule of Investments [Line Items]
Accounts receivable		$ 3,700,000
Noncontrolling Interest, Ownership Percentage by Parent		87.50%
Revenue from Related Parties		$ 14,000,000
ART [Member]
Schedule of Investments [Line Items]
Debt Instrument, Basis Spread on Variable Rate	1.25%
Accounts receivable		16,200,000	20,100,000
Noncurrent asset		98,800,000	32,700,000
Accounts payable		32,000,000	22,300,000
Debt payable within one year		9,800,000	8,600,000
Debt payable after one year		38,300,000	33,800,000
Noncurrent liability		$ 98,800,000	$ 32,700,000