CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Millions	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
CONSOLIDATED STATEMENTS OF INCOME
Net sales	$ 10,973.8	$ 11,534.5	$ 9,721.0
Costs and expenses:
Cost of sales (exclusive of depreciation and amortization shown below)	7,644.4	8,253.0	6,933.2
Warehouse, delivery, selling, general and administrative	2,095.4	2,091.8	1,902.8
Depreciation and amortization	219.3	215.2	218.4
Impairment of long-lived assets	1.2	37.0	4.2
Total costs and expenses	9,960.3	10,597.0	9,058.6
Operating income	1,013.5	937.5	662.4
Other (income) expense:
Interest	85.0	86.2	73.9
Other (income) expense, net	(0.8)	0.7	4.7
Income before income taxes	929.3	850.6	583.8
Income tax provision (benefit)	223.2	208.8	(37.2)
Net income	706.1	641.8	621.0
Less: Net income attributable to noncontrolling interests	4.6	8.1	7.6
Net income attributable to Reliance	$ 701.5	$ 633.7	$ 613.4
Earnings per share attributable to Reliance stockholders:
Diluted earnings per common share (in dollars per share)	$ 10.34	$ 8.75	$ 8.34
Basic earnings per common share (in dollars per share)	$ 10.49	$ 8.85	$ 8.42
Shares used in computing earning per share:
Diluted (in shares)	67,855	72,441	73,539
Basic (in shares)	66,885	71,621	72,851
Cash dividends per share (in dollars per share)	$ 2.20	$ 2.00	$ 1.80