14. Leases (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019
Lessee, Lease, Description [Line Items]
Other Commitment	$ 1,600
Finance Lease, Right-Of-Use Asset, before Accumulated Amortization	11,400		$ 11,400
Finance Lease, Right-Of-Use Asset, Accumulated Amortization	4,300		4,200
Finance Lease, Right-Of-Use Asset, after Accumulated Amortization	$ 7,100		$ 7,200
Lessee, Operating Lease, Lease Not yet Commenced, Term of Contract	4 years
Lessee, Operating Lease, Liability, Payments, Remainder of Fiscal Year	$ 32,000
Finance Lease, Liability, Payments, Remainder of Fiscal Year	$ 1,200
Operating Lease, Weighted Average Remaining Lease Term	9 years		9 years
Finance Lease, Weighted Average Remaining Lease Term	18 years		18 years
Operating Lease, Weighted Average Discount Rate, Percent	4.10%		4.20%
Finance Lease, Liability, Current	$ 500		$ 500
Finance Lease, Liability, Noncurrent	11,000		11,200
Finance Lease, Liability	$ 11,500		$ 11,700
Finance Lease, Weighted Average Discount Rate, Percent	6.50%		6.50%
Lessee, Operating Lease, Liability, Payments, Due Year Two	$ 37,700
Finance Lease, Liability, Payments, Due Year Two	1,200
Lessee, Operating Lease, Liability, Payments, Due Year Three	30,500
Finance Lease, Liability, Payments, Due Year Three	1,100
Lessee, Operating Lease, Liability, Payments, Due Year Four	25,700
Finance Lease, Liability, Payments, Due Year Four	1,100
Lessee, Operating Lease, Liability, Payments, Due Year Five	23,000
Finance Lease, Liability, Payments, Due Year Five	1,100
Lessee, Operating Lease, Liability, Payments, Due after Year Five	105,000
Finance Lease, Liability, Payments, Due after Year Five	14,900
Lessee, Operating Lease, Liability, Payments, Due	253,900
Finance Lease, Liability, Payment, Due	20,600
Lessee, Operating Lease, Liability, Undiscounted Excess Amount	(44,000)
Finance Lease, Liability, Undiscounted Excess Amount	(9,100)
Operating lease right-of-use assets	200,487		$ 201,868
Operating Lease, Payments	11,400	$ 11,700
Operating Lease, Cost	12,600	12,400
Finance Lease, Right-of-Use Asset, Amortization	100	100
Finance Lease, Interest Expense	200	200
Finance Lease Cost	300	300
Sublease Income	700	700
Finance Lease, Interest Payment on Liability	200	200
Finance Lease, Principal Payments	100	200
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	10,800	1,400
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	0	$ 0
Current operating lease liabilities	34,440		35,365
Operating lease liabilities	175,452		176,018
Operating Lease, Liability	$ 209,900		$ 211,400
Minimum [Member]
Lessee, Lease, Description [Line Items]
Lessee Operating And Finance Leases Remaining Lease Term	1 year
Maximum [Member]
Lessee, Lease, Description [Line Items]
Lessee Operating And Finance Leases Remaining Lease Term	19 years