Employee Benefit Plans (Narrative) (Details) - USD ($) shares in Millions, $ in Millions		12 Months Ended
	Jul. 01, 2019	Jun. 30, 2021	Dec. 31, 2020	Jun. 30, 2020	Dec. 31, 2019	Jun. 30, 2019	Dec. 31, 2018	Jun. 30, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Vesting term options granted		4 years
Stock options - term for stock options granted, in years		10 years
Treasury stock, shares repurchased		8.2		6.2		6.5
Cash payments for Restricted Stock Units		$ 10.7		$ 34.6		$ 26.6
Aggregate intrinsic value of stock options outstanding and exercisable		237.0
Options, vested and expected to vest, exercisable, aggregate intrinsic value		$ 116.9
Weighted average remaining life of stock options outstanding and exercisable		7 years
Options, exercisable, weighted average remaining contractual term		6 years
Aggregate intrinsic value for options exercised		$ 58.6		78.0		78.2
Supplemental officers retirement plan freeze date	Jul. 01, 2019
Defined benefit plan, accumulated benefit obligation		2,135.0		2,167.5
Prior service credits recognized				17.0
Minimum age required for plan eligibility								55 years
Minimum amount of service required for plan eligibility								10 years
Defined benefit plan, benefit obligation, payment for settlement						48.2
Accumulated other comprehensive income net gains (losses), after tax		(145.8)
Accumulated other comprehensive income net prior service cost (credit), after tax		(2.5)
Amount to be amortized from accumulated other comprehensive income (loss) next fiscal year		6.6
Expected amortization of prior service cost (credit), next fiscal year		0.3
Plan assets		2,306.3		1,988.8		$ 1,910.5
Employer contributions		10.9		9.8
Additional estimated future contribution		10.0
Expected future plan benefit payment - 2022		120.4
Expected future plan benefit payment - 2023		112.9
Expected future plan benefit payment - 2024		120.0
Expected future plan benefit payment - 2025		111.0
Expected future plan benefit payment - 2026		115.7
Expected future plan benefit payment - 2027 to 2031		$ 643.7
Defined contribution plan, maximum annual contribution per employee, percent		50.00%
Highly compensated employee contribution percentage to retirement and saving plan		12.00%
Defined contribution plan, cost			$ 130.8		$ 112.7		$ 110.9
Time Based Restriced Stock granted during or after September 1, 2018
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Vesting term options granted		3 years
Performance Based Restricted Stock and Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Minimum percentage that will ultimately vest under performance-based restricted stock awards based on performance target		0.00%
Maximum percentage that will ultimately vest under performance-based restricted stock awards based on performance target		150.00%
Employee Stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Purchase price of common stock as percentage of market value		95.00%
Non-Vested Stock Options
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total remaining unrecognized compensation cost		$ 19.2
Weighted-average remaining requisite vesting period		2 years 2 months 12 days
Restricted Stock Units (RSUs)
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total remaining unrecognized compensation cost		$ 43.5
Weighted-average remaining requisite vesting period		1 year 7 months 6 days
Non-Vested Restricted Stock
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total remaining unrecognized compensation cost		$ 113.1
Weighted-average remaining requisite vesting period		1 year 9 months 18 days
Cash and cash equivalents | Level 1
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Plan assets		$ 8.2		$ 20.1
Minimum | Performance Based Restricted Stock and Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Performance period (years)		1 year
Maximum | Performance Based Restricted Stock and Units
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Vesting term options granted		38 months
Performance period (years)		3 years