Annual report pursuant to Section 13 and 15(d)

BENEFIT PLANS - Net Periodic Benefit Costs (Details)

v3.6.0.2
BENEFIT PLANS - Net Periodic Benefit Costs (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2016
Dec. 31, 2015
Dec. 31, 2014
Pension Benefits      
Components of net periodic benefit expense [Abstract]      
Service cost $ 4,100 $ 1,830 $ 1,740
Interest cost 26,992 31,937 32,398
Expected return on plan assets (40,895) (44,175) (45,783)
Amortization of prior service credit 0 0 0
Amortization of (gain) / loss 7,459 7,934 5,767
Settlements 9,495 12,645 11,200
Benefit costs 7,151 10,171 5,322
Post-Retirement Benefits      
Components of net periodic benefit expense [Abstract]      
Service cost 0 0 0
Interest cost 219 506 856
Expected return on plan assets 0 0 0
Amortization of prior service credit (1,968) (1,968) (1,609)
Amortization of (gain) / loss (288) (401) (571)
Settlements 0 (3,090) 0
Benefit costs $ (2,037) $ (4,953) $ (1,324)