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Accounts Receivable, Net of Reserve for Doubtful Receivables - Additional Information (Detail) - USD ($) | Mar. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | ---
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |  |
Gross accounts receivable | $ 620,275,000 | $ 601,667,000 |
Reserve for doubtful receivables | 14,677,000 | 11,530,000 | $ 15,192,000
Net accounts receivable | 605,598,000 | 590,137,000 |
Accounts receivable due after one year | 7,198,000 | 8,348,000 |
Accounts receivable from related parties | 1,121,000 | 1,980,000 |
Reserve for doubtful receivables from related parties | $ 0 | $ 0 |

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- Definition Amounts due from customers or clients, within one year of the balance sheet date (or the normal operating cycle, whichever is longer) for goods or services (including trade receivables) that have been delivered or sold in the normal course of business. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.3) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher SEC -Name Regulation S-X (SX) -Number 210 -Section 03 -Paragraph 3 -Subparagraph a, b -Article 5 + Details
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