Leases, Cost (Details) - USD ($)	12 Months Ended
	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Leases [Abstract]
Operating Lease Cost	$ 29,400,000
Sublease Income	1,900,000
Total Lease Cost	27,500,000
Cash Paid for Amounts Included in the Measurement of Lease Liabilities	$ 28,900,000
Weighted-Average Remaining Lease Term	7 years
Weighted-Average Discount Rate	4.60%
Operating Lease Cost Prior to ASC 842		$ 29,200,000	$ 27,500,000