Changes in AOCI by Component (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ (9,934)
Total Other Comprehensive Income	175	$ 208
Ending balance	(9,759)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(11,633)	(9,981)
Other comprehensive income before reclassifications	0	0
Amounts reclassified from AOCL	112	113
Total Other Comprehensive Income	112	113
Reclassification of certain tax effects from AOCL		(2,150)
Ending balance	(11,521)	(12,018)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	251	31
Other comprehensive income before reclassifications	0	0
Amounts reclassified from AOCL	0	0
Total Other Comprehensive Income	0	0
Reclassification of certain tax effects from AOCL		7
Ending balance	251	38
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1,448	1,178
Other comprehensive income before reclassifications	63	95
Amounts reclassified from AOCL	0	0
Total Other Comprehensive Income	63	95
Reclassification of certain tax effects from AOCL		0
Ending balance	1,511	1,273
Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(9,934)	(8,772)
Other comprehensive income before reclassifications	63	95
Amounts reclassified from AOCL	112	113
Total Other Comprehensive Income	175	208
Reclassification of certain tax effects from AOCL		(2,143)
Ending balance	$ (9,759)	$ (10,707)