Aggregate dividends declared during the period for each share of common stock outstanding.

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Carrying value as of the balance sheet date of dividends declared but unpaid on equity securities issued by the entity and outstanding. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer).

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The cash outflow associated with the acquisition of business during the period. The cash portion only of the acquisition price.

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Amount remaining of a stock repurchase plan authorized.

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Number of shares that have been repurchased and retired during the period.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Subsequent Events (Details) - USD ($) $ / shares in Units, $ in Millions			1 Months Ended	3 Months Ended	26 Months Ended
	Apr. 23, 2018	Apr. 03, 2018	Apr. 27, 2018	Mar. 31, 2018	Mar. 31, 2018
Subsequent Event
Subsequent Event [Line Items]
Cash paid to acquire inventory, real estate, equipment and intangible assets	$ 12.5	$ 26.1
Cash dividends declared per Class A and Class B share (in dollars per share)	$ 0.29
Dividends payable	$ 7.2
Class A common stock
Subsequent Event [Line Items]
Shares repurchased pursuant to repurchase authorizations (in shares)				50,000	1,092,725
Class A common stock \| Subsequent Event
Subsequent Event [Line Items]
Shares repurchased pursuant to repurchase authorizations (in shares)			40,000
Average purchase price per share (in dollars per share)			$ 96.78
2016 Share Repurchase Authorization \| Class A common stock
Subsequent Event [Line Items]
Remaining authorized repurchase amount				$ 157.6	$ 157.6
2016 Share Repurchase Authorization \| Class A common stock \| Subsequent Event
Subsequent Event [Line Items]
Remaining authorized repurchase amount			$ 153.7