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Employee Benefit Plans - Fair Value of Plan Assets (Details) - USD ($) $ in Thousands | 12 Months Ended |
--- | --- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Defined Benefit Plan Disclosure [Line Items] |  |  |
Defined Benefit Plan Fair Value Of Plan Assets Gross | $ 154,673 | $ 162,890 |
Sales |  | (456) |
Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 21,283 | 4,592 | $ 4,354
Defined Benefit Plan, Plan Assets Level 3 Reconciliation, Increase (Decrease) for Actual Return (Loss) on Plan Assets Sold |  | 28 |
Actual return on plan assets still held | (29) | 280 |
Sales | 16,975 |  |
Foreign currency translation | (255) | 386 |
Other plan assets [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets |  | 4,592 |
Supplemental Employee Retirement Plans, Defined Benefit [Member] | Nonqualified Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 | 0
Foreign currency translation | 0 | 0 |
Other Postretirement Benefit Plans, Defined Benefit [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 | 0
Foreign currency translation | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 488,900 | 617,840 | 562,564
Defined Benefit Plan Fair Value Of Plan Assets Gross | 267,762 | 209,271 |
Business divestitures | (3,813) | 0 |
Foreign currency translation | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 3,652 | 3,988 |
Defined Benefit Plan Fair Value Of Plan Assets Gross | 3,652 | 3,988 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 264,110 | 205,283 |
Defined Benefit Plan Fair Value Of Plan Assets Gross | 264,110 | 205,283 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Corporate bonds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 150,179 | 74,509 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Corporate bonds [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Corporate bonds [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 150,179 | 74,509 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Government securities [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 115,517 | 133,540 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Government securities [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 1,586 | 2,766 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Government securities [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 113,931 | 130,774 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Private Placement [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 2,066 | 1,222 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Private Placement [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 2,066 | 1,222 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Private Placement [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Collective funds at NAV [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 175,963 | 352,481 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Collective funds at NAV [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Collective funds at NAV [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Real estate funds [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 32,686 | 48,294 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Real estate funds [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Real estate funds [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 12,489 | 7,794 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Cash and Cash Equivalents [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Domestic Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Cash and Cash Equivalents [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 162,589 | 175,534 | $ 148,514
Defined Benefit Plan Fair Value Of Plan Assets Gross | 103,906 | 109,403 |
Business divestitures | (13,285) | 0 |
Foreign currency translation | 11,223 | 10,491 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 52,436 | 67,469 |
Defined Benefit Plan Fair Value Of Plan Assets Gross | 52,436 | 67,469 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 30,187 | 37,342 |
Defined Benefit Plan Fair Value Of Plan Assets Gross | 30,187 | 37,342 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 21,283 | 4,592 |
Defined Benefit Plan Fair Value Of Plan Assets Gross | 21,283 | 4,592 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Collective funds at NAV [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 54,505 | 61,648 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Collective funds at NAV [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 |  |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Collective funds at NAV [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Collective funds at NAV [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Cash and Cash Equivalents [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 470 | 4,633 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Cash and Cash Equivalents [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 470 | 4,633 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Cash and Cash Equivalents [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Cash and Cash Equivalents [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Common stocks [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 28,528 | 28,761 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Common stocks [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 28,528 | 28,761 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Common stocks [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Common stocks [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Fixed income investments [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 27,797 | 29,612 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Fixed income investments [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Fixed income investments [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 27,797 | 29,612 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Fixed income investments [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Mutual Fund [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 23,438 | 38,717 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Mutual Fund [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 23,438 | 34,075 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Mutual Fund [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 4,642 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Mutual Fund [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Other plan assets [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 23,673 | 7,680 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Other plan assets [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Other plan assets [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 2,390 | 3,088 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Other plan assets [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 21,283 |  |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Net Asset Value (NAV) Other [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 4,178 | 4,483 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Net Asset Value (NAV) Other [Member] | Level 1 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 |  |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Net Asset Value (NAV) Other [Member] | Level 2 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | 0 | 0 |
Foreign Plan [Member] | Pension Plan [Member] | Qualified Plan [Member] | Net Asset Value (NAV) Other [Member] | Level 3 [Member] |  |  |
Defined Benefit Plan Disclosure [Line Items] |  |  |
Fair Value of Plan Assets | $ 0 | $ 0 |

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- Definition Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=112275985&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=108410482&loc=d3e1928-114920 + Details
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