Summary of Significant Accounting Policies - Components of Calculation of Basic Net Income Per Ordinary Share and Diluted Net Income Per Ordinary Share (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended		6 Months Ended
	Sep. 30, 2017	Oct. 01, 2016	Sep. 30, 2017	Oct. 01, 2016
Numerator:
Net income attributable to MKHL	$ 202.9	$ 160.9	$ 328.4	$ 308.0
Denominator:
Basic weighted average shares (in shares)	151,781,340	166,695,631	153,134,119	170,427,101
Weighted average dilutive share equivalents:
Share options, restricted shares/units, and performance restricted share units (in shares)	2,386,754	2,144,336	2,385,687	2,299,758
Diluted weighted average shares (in shares)	154,168,094	168,839,967	155,519,806	172,726,859
Basic net income per share (in dollars per share)	$ 1.34	$ 0.97	$ 2.14	$ 1.81
Diluted net income per share (in dollars per share)	$ 1.32	$ 0.95	$ 2.11	$ 1.78