Goodwill and Other Intangible Assets, net - Changes in the Carrying Amount of Goodwill (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2018	Mar. 20, 2018	Dec. 31, 2017	Dec. 31, 2016
Changes in the carrying amount of goodwill
Goodwill, Balance at the beginning of the period	$ 1,452.1
Goodwill acquired during the year	5.4
Measurement period adjustments	(7.8)
Currency translation and other	(1.7)
Goodwill, Balance at the end of the period	1,448.0
Aggregate purchase price of acquisitions	20.0
Carlisle Construction Materials
Changes in the carrying amount of goodwill
Goodwill, Balance at the beginning of the period	544.3
Goodwill acquired during the year	2.8
Measurement period adjustments	(7.8)
Currency translation and other	(1.4)
Goodwill, Balance at the end of the period	537.9
Carlisle Interconnect Technologies
Changes in the carrying amount of goodwill
Goodwill, Balance at the beginning of the period	640.3
Goodwill acquired during the year	2.6
Measurement period adjustments	0.0
Currency translation and other	0.3
Goodwill, Balance at the end of the period	643.2
Carlisle Fluid Technologies
Changes in the carrying amount of goodwill
Goodwill, Balance at the beginning of the period	171.0
Goodwill acquired during the year	0.0
Measurement period adjustments	0.0
Currency translation and other	(0.6)
Goodwill, Balance at the end of the period	170.4
Carlisle Brake & Friction
Changes in the carrying amount of goodwill
Goodwill, Balance at the beginning of the period	96.5
Goodwill acquired during the year	0.0
Measurement period adjustments	0.0
Currency translation and other	0.0
Goodwill, Balance at the end of the period	$ 96.5
Goodwill, accumulated impairment loss				$ 130.0
Carlisle Food Service Products
Goodwill
Goodwill reclassified to discontinued operations		$ 149.7	$ 149.7
Other intangible assets, net, allocated to discontinued operations		$ 169.4	$ 169.4