CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Parenthetical) - USD ($) $ in Thousands |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2016 |
Sep. 30, 2015 |
Sep. 30, 2016 |
Sep. 30, 2015 |
|
| Statement of Comprehensive Income [Abstract] | ||||
| Benefit plan liabilities, tax | $ (174) | $ (211) | $ (250) | $ (755) |
| Fair value change of derivatives, tax | $ (676) | $ 170 | $ 129 | $ 830 |