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Employee Benefit Plans - Schedule of Defined Benefit Plan Assets (Detail) $ in Thousands | Dec. 31, 2017 USD ($)
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Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, amount | $ 8,152
Defined benefit plan assets, percentage | 100.00%
Cash [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, amount | $ 561
Defined benefit plan assets, percentage | 7.00%
Debt Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, amount | $ 5,242
Defined benefit plan assets, percentage | 64.00%
Equity Securities [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, amount | $ 1,367
Defined benefit plan assets, percentage | 17.00%
Other [Member] |
Defined Benefit Plan Disclosure [Line Items] |
Defined benefit plan assets, amount | $ 982
Defined benefit plan assets, percentage | 12.00%

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- Definition Amount of asset, recognized in statement of financial position, for overfunded defined benefit pension and other postretirement plans. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1731-114919 Reference 3: 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(17)) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=64852052&loc=d3e1703-114919 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.7-03(a)(10)) -URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(10)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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- Definition 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. + References No definition available. + Details
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