Accumulated Other Comprehensive Earnings (Loss) (Details) - USD ($) $ in Thousands | 6 Months Ended |
Jun. 30, 2018 | Jun. 30, 2017 |
Accumulated other comprehensive earnings (loss), net of tax | | |
Balance at the beginning of the period | $ 733,840 | |
Adoption of ASU 2018-02 (See Note 1) | 2,726 | |
Balance at the end of the period | 726,110 | $ 703,433 |
Foreign Currency Derivatives | Foreign currency forward contracts | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Balance at the beginning of the period | 51 | (76) |
Other comprehensive earnings (loss) before reclassifications | (9) | 95 |
Reclassifications from accumulated other comprehensive loss | (51) | 34 |
Other comprehensive earnings (loss) net of tax | (60) | 129 |
Balance at the end of the period | | 53 |
Foreign Currency Derivatives | Foreign currency forward contracts | New Accounting Pronouncement, Early Adoption, Effect | ASU 2018-02 | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Adoption of ASU 2018-02 (See Note 1) | 9 | |
Foreign Currency Derivatives | Commodity futures contracts | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Balance at the beginning of the period | 20 | 1,114 |
Other comprehensive earnings (loss) before reclassifications | (1,393) | (1,213) |
Reclassifications from accumulated other comprehensive loss | 684 | (122) |
Other comprehensive earnings (loss) net of tax | (709) | (1,335) |
Balance at the end of the period | (685) | (221) |
Foreign Currency Derivatives | Commodity futures contracts | New Accounting Pronouncement, Early Adoption, Effect | ASU 2018-02 | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Adoption of ASU 2018-02 (See Note 1) | 4 | |
Investments | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Balance at the beginning of the period | (889) | (697) |
Other comprehensive earnings (loss) before reclassifications | (970) | 242 |
Other comprehensive earnings (loss) net of tax | (970) | 242 |
Balance at the end of the period | (2,027) | (455) |
Investments | New Accounting Pronouncement, Early Adoption, Effect | ASU 2018-02 | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Adoption of ASU 2018-02 (See Note 1) | (168) | |
Postretirement and Pension Benefits | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Balance at the beginning of the period | 3,289 | 4,873 |
Other comprehensive earnings (loss) before reclassifications | | 4 |
Reclassifications from accumulated other comprehensive loss | (502) | (466) |
Other comprehensive earnings (loss) net of tax | (502) | (462) |
Balance at the end of the period | 3,535 | 4,411 |
Postretirement and Pension Benefits | New Accounting Pronouncement, Early Adoption, Effect | ASU 2018-02 | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Adoption of ASU 2018-02 (See Note 1) | 748 | |
Foreign Currency Translation Adjustment | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Balance at the beginning of the period | (24,262) | (25,460) |
Other comprehensive earnings (loss) before reclassifications | (62) | 3,091 |
Other comprehensive earnings (loss) net of tax | (62) | 3,091 |
Balance at the end of the period | (24,324) | (22,369) |
Accumulated Other Comprehensive Earnings ( Loss ) | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Balance at the beginning of the period | (21,791) | (20,246) |
Other comprehensive earnings (loss) before reclassifications | (2,434) | 2,219 |
Reclassifications from accumulated other comprehensive loss | 131 | (554) |
Other comprehensive earnings (loss) net of tax | (2,303) | 1,665 |
Balance at the end of the period | (23,501) | $ (18,581) |
Accumulated Other Comprehensive Earnings ( Loss ) | New Accounting Pronouncement, Early Adoption, Effect | ASU 2018-02 | | |
Accumulated other comprehensive earnings (loss), net of tax | | |
Adoption of ASU 2018-02 (See Note 1) | $ 593 | |