Short-Term Borrowings (Details) - USD ($)	9 Months Ended
	Sep. 30, 2020	Dec. 31, 2019
Short-term Debt [Line Items]
Line of Credit Facility, Commitment Fee Percentage	17.50%
Ratio of Indebtedness to Net Capital	0.65
Notional Amount of Nonderivative Instruments	$ 100,000,000.0
Number of short-term lines of Credit, rate swap	3
Line of Credit Facility, Maximum Borrowing Capacity	$ 375,000,000.0
Line of Credit Facility, Remaining Borrowing Capacity	154,700,000
Bank Overdrafts	900,000	$ 3,200,000
Short-term borrowing	$ 216,388,000	$ 247,371,000
Short-term Debt, Weighted Average Interest Rate, at Point in Time	1.28%	2.62%
Committed Line of Credit Facility Two [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	LIBOR rate, plus 0.75 percent
Committed Line of Credit Facility Three [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	Lender's base rate, plus 0.75 percent
Committed Line of Credit Facility Five [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	Lender's base rate, plus 0.85 percent
Committed Line of Credit Facility Four [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	LIBOR rate, plus 1.125 percent
Committed Line of Credit Facility Six [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	LIBOR rate, plus 1.75 percent
Committed Line of Credit Facility Seven [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	LIBOR rate, plus 1.75 percent
Committed Line of Credit Facility Eight [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	LIBOR rate, plus 1.75 percent
Committed Line of Credit Facility Nine [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	LIBOR rate, plus 1.75 percent
Debt Instrument, Description of Variable Rate Basis	112.50%
Interest Rate Swap Rate, Low Range [Member]
Short-term Debt [Line Items]
Fixed Swap Rate	26.15%
Interest Rate Swap Rate, High Range [Member]
Short-term Debt [Line Items]
Fixed Swap Rate	38.75%
Committed Line of Credit Facility One [Member]
Short-term Debt [Line Items]
Debt Instrument, Description of Variable Rate Basis	LIBOR rate, plus 0.75 percent