Changes in AOCI by Component (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance			$ (9,934)
Total Other Comprehensive Income	$ 26	$ 199	201	$ 407
Ending balance	(9,733)		(9,733)
Accumulated Net Gain (Loss) from Cash Flow Hedges Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(11,521)	(12,018)	(11,633)	(9,981)
Other comprehensive income before reclassifications	0	0	0	0
Amounts reclassified from AOCL	113	113	225	226
Total Other Comprehensive Income	113	113	225	226
Reclassification of certain tax effects from AOCL		(2,150)		(2,150)
Ending balance	(11,408)	(11,905)	(11,408)	(11,905)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	251	38	251	31
Other comprehensive income before reclassifications	0	0	0	0
Amounts reclassified from AOCL	0	0	0	0
Total Other Comprehensive Income	0	0	0	0
Reclassification of certain tax effects from AOCL		7		7
Ending balance	251	38	251	38
Accumulated Foreign Currency Adjustment Attributable to Parent [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	1,511	1,273	1,448	1,178
Other comprehensive income before reclassifications	(87)	86	(24)	181
Amounts reclassified from AOCL	0	0	0	0
Total Other Comprehensive Income	(87)	86	(24)	181
Reclassification of certain tax effects from AOCL		0		0
Ending balance	1,424	1,359	1,424	1,359
Comprehensive Income (Loss) [Member]
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(9,759)	(10,707)	(9,934)	(8,772)
Other comprehensive income before reclassifications	(87)	86	(24)	181
Amounts reclassified from AOCL	113	113	225	226
Total Other Comprehensive Income	26	199	201	407
Reclassification of certain tax effects from AOCL		(2,143)		(2,143)
Ending balance	$ (9,733)	$ (10,508)	$ (9,733)	$ (10,508)