Carrying value as of the balance sheet date of liabilities incurred (and for which invoices have typically been received) and payable to vendors for goods and services received that are used in an entity's business. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

Name:	us-gaap_AccountsPayableCurrent
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Amount due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer), for goods or services (including trade receivables) that have been delivered or sold in the normal course of business, reduced to the estimated net realizable fair value by an allowance established by the entity of the amount it deems uncertain of collection.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 606
-SubTopic 10
-Section 50
-Paragraph 8
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=109196051&loc=SL49130549-203045

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(3))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

Financial Information for Subsidiary and Guarantor Parent (B.S.) (Details) - USD ($) $ in Millions	Jun. 30, 2018	Jan. 01, 2018	Dec. 31, 2017	Jun. 30, 2017	Dec. 31, 2016
ASSETS
Cash and cash equivalents	$ 122.4		$ 141.6	$ 154.6	$ 229.6
Accounts receivable, net	621.9		545.3
Intercompany notes receivable	0.0		0.0
Short-term contract assets	47.7	$ 36.5	0.0
Inventories, net	1,254.1		1,176.1
Prepaid expenses and other current assets	80.2		52.7
Total current assets	2,126.3		1,915.7
Property, plant and equipment, net	2,479.0		2,495.7
Goodwill	531.0		531.4
Intercompany notes receivable	0.0		0.0
Long-term contract assets	0.1	16.9
Investment in subsidiaries	0.0		0.0
Other assets	257.0		242.6
Total assets	5,393.3		5,185.4
LIABILITIES AND EQUITY
Accounts payable	429.3		420.1
Accrued liabilities	225.3		282.4
Intercompany notes payable	0.0		0.0
Short-term contract liabilities	70.4	69.7	0.0
Short-term debt and current portion of long-term debt	16.3		10.1
Total current liabilities	741.3		712.6
Long-term debt	1,535.5		1,530.6
Intercompany notes payable	0.0		0.0
Accrued postretirement benefits	306.1		317.8
Pension liabilities	677.6		697.0
Deferred income taxes	9.7		9.7
Long-term contract liabilities	14.6	$ 22.2	0.0
Other long-term liabilities	66.6		73.2
Total liabilities	3,351.4		3,340.9
Total stockholders’ equity	2,041.9		1,844.5	$ 1,514.4	$ 1,444.8
Total Liabilities and Equity	5,393.3		5,185.4
Reportable Legal Entities \| Parent Company
ASSETS
Cash and cash equivalents	1.9		2.1
Accounts receivable, net	0.0		0.2
Intercompany notes receivable	0.0		0.0
Short-term contract assets	0.0
Inventories, net	0.0		0.0
Prepaid expenses and other current assets	12.2		6.6
Total current assets	14.1		8.9
Property, plant and equipment, net	0.9		0.9
Goodwill	0.0		0.0
Intercompany notes receivable	0.0		0.0
Investment in subsidiaries	6,008.5		5,645.6
Other assets	27.3		25.4
Total assets	6,050.8		5,680.8
LIABILITIES AND EQUITY
Accounts payable	3.2		3.0
Accrued liabilities	54.6		54.1
Intercompany notes payable	2,019.9		1,836.5
Short-term contract liabilities	0.0
Short-term debt and current portion of long-term debt	0.2		0.3
Total current liabilities	2,077.9		1,893.9
Long-term debt	1,276.9		1,275.7
Intercompany notes payable	0.0		0.0
Accrued postretirement benefits	0.0		0.0
Pension liabilities	626.4		644.3
Deferred income taxes	9.7		9.7
Long-term contract liabilities	0.0
Other long-term liabilities	18.0		12.7
Total liabilities	4,008.9		3,836.3
Total stockholders’ equity	2,041.9		1,844.5
Total Liabilities and Equity	6,050.8		5,680.8
Reportable Legal Entities \| Subsidiary
ASSETS
Cash and cash equivalents	9.1		13.5
Accounts receivable, net	193.9		141.6
Intercompany notes receivable	0.0		0.0
Short-term contract assets	0.0
Inventories, net	233.4		207.9
Prepaid expenses and other current assets	33.5		4.5
Total current assets	469.9		367.5
Property, plant and equipment, net	1,556.8		1,581.6
Goodwill	0.0		0.0
Intercompany notes receivable	0.0		0.0
Investment in subsidiaries	37.7		37.7
Other assets	34.8		18.0
Total assets	2,099.2		2,004.8
LIABILITIES AND EQUITY
Accounts payable	177.9		180.3
Accrued liabilities	60.9		88.5
Intercompany notes payable	1,788.3		1,669.1
Short-term contract liabilities	32.9
Short-term debt and current portion of long-term debt	1.0		0.6
Total current liabilities	2,061.0		1,938.5
Long-term debt	152.2		150.7
Intercompany notes payable	200.0		200.0
Accrued postretirement benefits	245.8		250.2
Pension liabilities	4.1		4.4
Deferred income taxes	0.0		0.0
Long-term contract liabilities	0.0
Other long-term liabilities	17.5		17.2
Total liabilities	2,680.6		2,561.0
Total stockholders’ equity	(581.4)		(556.2)
Total Liabilities and Equity	2,099.2		2,004.8
Reportable Legal Entities \| NonGuarantor Subsidiaries
ASSETS
Cash and cash equivalents	111.4		126.0
Accounts receivable, net	428.0		403.5
Intercompany notes receivable	3,808.2		3,505.6
Short-term contract assets	47.7
Inventories, net	1,020.7		968.2
Prepaid expenses and other current assets	34.5		41.6
Total current assets	5,450.5		5,044.9
Property, plant and equipment, net	921.3		913.2
Goodwill	531.0		531.4
Intercompany notes receivable	200.0		200.0
Investment in subsidiaries	0.0		0.0
Other assets	194.9		199.2
Total assets	7,297.7		6,888.7
LIABILITIES AND EQUITY
Accounts payable	248.2		236.8
Accrued liabilities	109.8		139.8
Intercompany notes payable	0.0		0.0
Short-term contract liabilities	37.5
Short-term debt and current portion of long-term debt	15.1		9.2
Total current liabilities	410.6		385.8
Long-term debt	106.4		104.2
Intercompany notes payable	0.0		0.0
Accrued postretirement benefits	60.3		67.6
Pension liabilities	47.1		48.3
Deferred income taxes	0.0		0.0
Long-term contract liabilities	14.6
Other long-term liabilities	31.1		43.3
Total liabilities	670.1		649.2
Total stockholders’ equity	6,627.6		6,239.5
Total Liabilities and Equity	7,297.7		6,888.7
Eliminations
ASSETS
Cash and cash equivalents	0.0		0.0
Accounts receivable, net	0.0		0.0
Intercompany notes receivable	(3,808.2)		(3,505.6)
Short-term contract assets	0.0
Inventories, net	0.0		0.0
Prepaid expenses and other current assets	0.0		0.0
Total current assets	(3,808.2)		(3,505.6)
Property, plant and equipment, net	0.0		0.0
Goodwill	0.0		0.0
Intercompany notes receivable	(200.0)		(200.0)
Investment in subsidiaries	(6,046.2)		(5,683.3)
Other assets	0.0		0.0
Total assets	(10,054.4)		(9,388.9)
LIABILITIES AND EQUITY
Accounts payable	0.0		0.0
Accrued liabilities	0.0		0.0
Intercompany notes payable	(3,808.2)		(3,505.6)
Short-term contract liabilities	0.0
Short-term debt and current portion of long-term debt	0.0		0.0
Total current liabilities	(3,808.2)		(3,505.6)
Long-term debt	0.0		0.0
Intercompany notes payable	(200.0)		(200.0)
Accrued postretirement benefits	0.0		0.0
Pension liabilities	0.0		0.0
Deferred income taxes	0.0		0.0
Long-term contract liabilities	0.0
Other long-term liabilities	0.0		0.0
Total liabilities	(4,008.2)		(3,705.6)
Total stockholders’ equity	(6,046.2)		(5,683.3)
Total Liabilities and Equity	$ (10,054.4)		$ (9,388.9)