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Significant Accounting Policies - Additional Information (Detail) - USD ($) $ in Thousands | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Summary Of Significant Accounting Policies [Line Items] |  |  |
Cash and cash equivalents maturity period, maximum |  | 90 days |
Accounting Standards Update 2015-17 [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Reclassification from current to noncurrent assets |  |  | $ (9,279)
ASU 2016-09 [Member] | Subsequent Event [Member] |  |  |
Summary Of Significant Accounting Policies [Line Items] |  |  |
Income tax expense | $ 1,000 |  |

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- Definition Amount of cumulative effect of the change in accounting principle or new accounting pronouncement on retained earnings or other components of equity or net assets in the statement of financial position as of the beginning of the earliest period presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Direct Effects of a Change in Accounting Principle -URI http://asc.fasb.org/extlink&oid=66092750 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22580-107794 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Indirect Effects of a Change in Accounting Principle -URI http://asc.fasb.org/extlink&oid=6515603 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Accounting Change -URI http://asc.fasb.org/extlink&oid=6503790 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Retrospective Application -URI http://asc.fasb.org/extlink&oid=6523989 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (b)(3) -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22499-107794 Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 250 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64853466&loc=d3e22583-107794 Reference 8: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Change in Accounting Principle -URI http://asc.fasb.org/extlink&oid=6507316 + Details
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