Consolidated Statements of Cash Flows - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Cash flows from operating activities:
Net earnings	$ 154.8	$ 104.7	$ 94.2
Adjustments to reconcile earnings to net cash provided by operating activities:
Depreciation and amortization	89.2	89.2	118.3
Write off of debt financing costs		1.1
Loss (gain) on disposal of discontinued operations	74.1	(0.1)	0.2
Deferred income taxes	(12.3)	51.0	(48.5)
Share-based compensation	10.2	12.4	13.4
Equity earnings from joint venture	(67.0)	(73.1)	(66.1)
Separation costs		34.5	34.3
Loss on interest rate swap		10.7
U.S. pension (credit) expense	(4.5)	15.0	25.2
Non-cash foreign currency translation on intercompany loans	(2.6)	(3.6)	19.8
Other, non-cash adjustments, net	2.2	(0.3)	0.3
Changes in operating assets and liabilities:
Receivables	(37.1)	(23.9)	2.7
Inventories	3.6	(7.0)	(15.7)
Other current assets	2.2	7.1	(7.3)
Other noncurrent assets	(1.6)	(9.9)	7.9
Accounts payable and accrued expenses	(20.0)	(82.1)	15.0
Income taxes payable	(18.8)	(49.3)	33.6
Other long-term liabilities	(1.2)	(22.0)	(22.2)
Other, net	(0.8)	(5.1)	(1.4)
Net cash provided by operating activities	170.4	49.3	203.7
Cash flows from investing activities:
Purchases of property, plant and equipment	(89.7)	(104.2)	(170.7)
Return of investment from joint venture	69.1	86.9	64.2
Cash paid for acquisition	(31.2)
Payment of company-owned life insurance, net	(2.4)		2.2
Other investing activities		0.3	2.8
Net cash (used for) investing activities	(54.2)	(17.0)	(101.5)
Cash flows from financing activities:
Proceeds from revolving credit facility and other short-term debt	103.0	90.0
Payments of revolving credit facility and other short-term debt	(103.0)	(90.0)
Proceeds from long-term debt		363.5
Payments of long-term debt	(25.0)	(434.1)	(39.5)
Financing costs	(0.6)	(8.1)
Special dividends paid			(1.2)
Proceeds from exercised stock options	3.3	0.7	6.4
Cash transferred to Armstrong Flooring, Inc.		(9.1)
Proceeds from company-owned life insurance loans, net		2.0	2.0
Payment for treasury stock acquired	(80.4)	(43.8)
Net cash (used for) financing activities	(102.7)	(128.9)	(32.3)
Effect of exchange rate changes on cash and cash equivalents	4.2	(6.3)	(10.4)
Net increase (decrease) in cash and cash equivalents	17.7	(102.9)	59.5
Cash and cash equivalents at beginning of year	141.9	244.8	185.3
Cash and cash equivalents at end of year	159.6	141.9	244.8
Cash and cash equivalents at end of year of discontinued operations			35.5
Cash and cash equivalents at end of year of continuing operations	159.6	141.9	209.3
Supplemental Cash Flow Disclosures:
Interest paid	30.7	33.4	39.4
Income taxes paid, net	32.1	33.7	44.4
Amounts in accounts payable for capital expenditures	$ 2.6	$ 4.4	$ 14.3