Represents the amount of minimum lease payments for direct financing.

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Represents the amount of minimum lease payments maturing in the fifth fiscal year following the latest fiscal year for direct financing.

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Represents the amount of minimum lease payments maturing in the fourth fiscal year following the latest fiscal year for direct financing.

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No definition available.

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Represents the amount of minimum lease payments maturing in the third fiscal year following the latest fiscal year for direct financing.

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No definition available.

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Represents the amount of minimum lease payments maturing after the fifth fiscal year following the latest fiscal year for direct financing.

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Area of a real estate property.

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Amount of minimum lease payments for capital leases.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 840
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=84164817&loc=d3e45280-112737

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Amount of minimum lease payments for capital leases due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of minimum lease payments for capital leases due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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-Name Accounting Standards Codification
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Amount of required minimum rental payments for operating leases having an initial or remaining non-cancelable lease term in excess of one year due in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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-Publisher FASB
-Name Accounting Standards Codification
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Commitments and Contingencies (Details) $ in Thousands	12 Months Ended
Commitments and Contingencies (Details) $ in Thousands	Dec. 31, 2018 USD ($) ft²	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)
Rent expense	$ 9,400	$ 8,200	$ 5,400
Future non-cancelable minimum payments under operating leases
2019	12,909
2020	8,589
2021	3,899
2022	2,011
2023	1,155
Total minimum lease payments	28,563
Future non-cancelable minimum payments under capital leases
2019	688
2020	472
Total minimum lease payments	1,160
Future non-cancelable minimum payments under direct financing
2021	466
2022	2,793
2023	2,793
Thereafter	35,850
Total minimum lease payments	$ 41,902
Chadds Ford, Pennsylvania
Office leases
Square footage \| ft²	112,000
Wilmington, Delaware
Office leases
Square footage \| ft²	100,000
Europe and Japan
Office leases
Square footage \| ft²	63,000