Commitments and Contingencies (Operating Lease Payments) (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019
Operating Leased Assets [Line Items]
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	$ 46,500	$ 17,000
Operating Lease, Weighted Average Discount Rate, Percent	2.90%	4.70%
Operating Lease, Weighted Average Remaining Lease Term	4 years 6 months	4 years 7 months 6 days
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2017	$ 19,460
Total minimum lease payments	68,912
lessee, operating lease, interest due	(4,348)
Operating Lease, Liability, Current	17,784	$ 12,857
Operating Lease, Liability, Noncurrent	51,128	30,334
Operating Lease, Payments	17,300	$ 19,700
Property Subject to Operating Lease [Member]
Operating Leases, Future Minimum Payments Due, Fiscal Year Maturity [Abstract]
2018	15,183
2019	13,941
2020	12,637
2021	8,691
2022 and beyond	3,348
Lessee, Operating Lease, Liability, Payments, Due	$ 73,260

lessee, operating lease, interest due

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Amount of lessee's undiscounted obligation for lease payment for operating lease.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 50
-Paragraph 6
-URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980

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Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in fourth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

+ References

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Present value of lessee's discounted obligation for lease payments from operating lease.

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-Publisher FASB
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Present value of lessee's discounted obligation for lease payments from operating lease, classified as current.

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Present value of lessee's discounted obligation for lease payments from operating lease, classified as noncurrent.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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-Publisher FASB
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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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No definition available.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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