Segment Information (Segment Reconciliation) (Details) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2015
Segment Reporting Information [Line Items]
REVENUES	$ 176,549	$ 148,353	$ 353,934	$ 295,378
Customer revenues	176,549	148,353	353,934	295,378
Depreciation and amortization expense	33,132	31,400	65,666	60,393
Net unallocated interest expense	(2,633)	(2,839)	(5,332)	(5,904)
Net loss on financial instruments			300	(300)
Net gain on financial instruments	5,558	264	5,030	251
Pre-tax earnings from continuing operations	18,763	17,243	30,911	31,716
Assets	1,151,680		1,151,680		$ 1,041,721
Customer Revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	176,549	148,353	353,934	295,378
Customer revenues	176,549	148,353	353,934	295,378
CAM [Member]
Segment Reporting Information [Line Items]
REVENUES	47,439	45,632	99,165	88,486
Customer revenues	47,439	45,632	99,165	88,486
Depreciation and amortization expense	22,607	22,356	45,337	43,266
Segment earnings (loss)	16,229	14,441	35,739	28,879
Net unallocated interest expense	(2,600)	(2,400)	(4,900)	(5,000)
Assets	906,849		906,849		804,776
CAM [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	29,387	24,660	58,148	44,541
Customer revenues	29,387	24,660	58,148	44,541
ACMI Services [Member]
Segment Reporting Information [Line Items]
REVENUES	114,145	103,892	229,101	209,360
Customer revenues	114,145	103,892	229,101	209,360
Depreciation and amortization expense	10,228	9,027	19,772	17,118
Segment earnings (loss)	(7,130)	1,126	(17,486)	(1,445)
Assets	158,183		158,183		154,852
ACMI Services [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	114,145	103,892	229,101	209,360
Customer revenues	114,145	103,892	229,101	209,360
All other [Member]
Segment Reporting Information [Line Items]
REVENUES	57,253	32,179	112,264	67,785
Customer revenues	57,253	32,179	112,264	67,785
Depreciation and amortization expense	297	17	557	9
Segment earnings (loss)	4,130	1,840	7,998	4,916
Assets	86,648		86,648		$ 82,093
All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	33,017	19,801	66,685	41,477
Customer revenues	33,017	19,801	66,685	41,477
Significant Reconciling Items [Member]
Segment Reporting Information [Line Items]
Net unallocated interest expense	(24)	(428)	(370)	885
Eliminate inter-segment revenues [Member]
Segment Reporting Information [Line Items]
REVENUES	(42,288)	(33,350)	(86,596)	(70,253)
Customer revenues	$ (42,288)	$ (33,350)	$ (86,596)	$ (70,253)