Segment Information Segment Reconciliation (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2015	Jun. 30, 2014	Jun. 30, 2015	Jun. 30, 2014	Dec. 31, 2014
Segment Reporting Information [Line Items]
REVENUES	$ 148,353	$ 149,618	$ 295,378	$ 293,211
Customer revenues	148,353	149,618	295,378	293,211
Depreciation and amortization expense	31,400	27,142	60,393	52,121
Net unallocated interest expense	(2,839)	(3,481)	(5,904)	(7,304)
Net gain (loss) on derivative instruments	264	31	251	330
Pre-tax earnings from continuing operations	17,243	14,691	31,716	25,022
Assets	1,025,163		1,025,163		$ 1,031,629
Customer Revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	148,353	149,618	295,378	293,211
Customer revenues	148,353	149,618	295,378	293,211
CAM [Member]
Segment Reporting Information [Line Items]
REVENUES	45,632	40,590	88,486	81,225
Customer revenues	45,632	40,590	88,486	81,225
Depreciation and amortization expense	22,356	20,328	43,266	38,673
Segment earnings (loss)	14,441	10,667	28,879	25,107
Net unallocated interest expense	(2,400)	(3,000)	(5,000)	(6,300)
Assets	785,686		785,686		801,195
CAM [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	24,660	17,839	44,541	36,253
Customer revenues	24,660	17,839	44,541	36,253
ACMI Services [Member]
Segment Reporting Information [Line Items]
REVENUES	103,892	111,304	209,360	219,900
Customer revenues	103,892	111,304	209,360	219,900
Depreciation and amortization expense	9,027	7,191	17,118	14,026
Segment earnings (loss)	1,126	309	(1,445)	(6,737)
Assets	140,372		140,372		135,109
ACMI Services [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	103,892	111,304	209,360	219,900
Customer revenues	103,892	111,304	209,360	219,900
All other [Member]
Segment Reporting Information [Line Items]
REVENUES	32,179	36,493	67,785	63,301
Customer revenues	32,179	36,493	67,785	63,301
Depreciation and amortization expense	17	(377)	9	(578)
Segment earnings (loss)	1,840	4,108	4,916	7,125
Assets	99,105		99,105		$ 95,325
All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	19,801	20,475	41,477	37,058
Customer revenues	19,801	20,475	41,477	37,058
Eliminate inter-segment revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	(33,350)	(38,769)	(70,253)	(71,215)
Customer revenues	(33,350)	(38,769)	(70,253)	(71,215)
Significant Reconciling Items [Member]
Segment Reporting Information [Line Items]
Net unallocated interest expense	$ (428)	$ (424)	$ (885)	$ (803)