Consolidated Statements Of Comprehensive Income (Loss) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Comprehensive Income (Loss), Net of Tax, Attributable to Parent [Abstract]
Net earnings	$ 101.2us-gaap_ProfitLoss	$ 199.7us-gaap_ProfitLoss	$ 250.5us-gaap_ProfitLoss
Other comprehensive income (loss), net of tax:
Foreign currency translation adjustments	(71.7)	(5.0)	16.0
Cash flow hedges	3.4	2.0	(4.0)
Defined benefit pension plans	(29.0)	26.7	(6.1)
Other comprehensive income (loss)	(97.3)	23.7	5.9
Comprehensive income	3.9	223.4	256.4
Less: comprehensive (income) attributable to noncontrolling interest	(3.0)	(2.6)	(2.4)
Comprehensive income attributable to Leggett & Platt, Inc.	$ 0.9us-gaap_ComprehensiveIncomeNetOfTax	$ 220.8us-gaap_ComprehensiveIncomeNetOfTax	$ 254.0us-gaap_ComprehensiveIncomeNetOfTax

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income (loss) and other comprehensive income (loss), attributable to noncontrolling interests. Excludes changes in equity resulting from investments by owners and distributions to owners.

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Amount after tax of (increase) decrease in the value of the projected benefit obligation related to a change in an actuarial assumption and increase (decrease) in the value of the plan assets resulting from experience different from that assumed, that has not been recognized in net periodic benefit (cost) credit.

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax and reclassification adjustments of other comprehensive income (loss).

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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