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Leases - Schedule of Lease Cash Flows (Details) - USD ($) $ in Thousands |  | 3 Months Ended
--- | --- | ---
Jan. 01, 2019 | Mar. 31, 2019 | Mar. 31, 2018
Cash paid for amounts included in the measurement of lease liabilities: |  |  |
Operating cash flows from operating leases |  | $ 4,755 |
Operating cash flows from finance leases |  | 16 |
Financing cash flows from finance leases |  | 1,063 |
Noncash activities from right-of-use assets obtained in exchange for lease obligations: |  |  |
Operating leases |  | 6,568 |
Finance leases |  | 453 |
Noncash activities from adoption of ASC 842 as of January 1, 2019 |  |  |
Prepaid expenses and other current assets | $ (884) | (3,031) | $ (16,770)
Operating lease assets | 54,069 | 55,408 |
Operating lease liabilities | 64,506 | $ 69,622 |
Accrued liabilities | $ (11,321) |  |

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- Definition Amount of interest paid on finance lease liability. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977 + Details
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- Definition Amount of cash outflow for principal payment on finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details
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