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Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended
--- | --- | ---
Jun. 30, 2018 | Jun. 30, 2017 | Jun. 30, 2018 | Jun. 30, 2017
Other Comprehensive Income (Loss), Net of Tax [Abstract] |  |  |  |
Net income | $ 22,837 | $ 12,769 | $ 31,189 | $ 16,765
Other comprehensive (loss) income: |  |  |  |
Foreign currency translation adjustment | (1,787) | 1,091 | (1,677) | 1,770
Cumulative effect of accounting change (see Note 2) | 0 | 0 | (350) | 0
Adjustment to retirement benefit liability, net of tax | (5) | (3) | (10) | (6)
Adjustment to post employment health care benefit liability, net of tax | 31 | 30 | 63 | 59
Other comprehensive (loss) income | (1,761) | 1,118 | (1,974) | 1,823
Total comprehensive income | $ 21,076 | $ 13,887 | $ 29,215 | $ 18,588

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