Commitments and Contingencies (Tables)

12 Months Ended

Dec. 31, 2018

Commitments and Contingencies Disclosure [Abstract]

Schedule of Future Minimum Rental Payments for Operating Leases [Table Text Block]

At December 31, 2018, the aggregate future minimum lease payments under all non-cancelable lease agreements were as follows:

(in thousands)
2019	$	48,292
2020	43,517
2021	34,836
2022	27,035
2023	19,981
Thereafter	36,349
Total minimum future lease payments	$	210,010

Rental expense in 2018, 2017 and 2016 for operating leases totaled $54.6 million, $51.0 million and $49.3 million, respectively.