Segment Information (Entity-Wide Disclosures) (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Segment Reporting Information [Line Items]
Customer revenues	$ 221,675	$ 193,261	$ 176,549	$ 177,385	$ 181,581	$ 142,305	$ 148,353	$ 147,025	$ 768,870	$ 619,264	$ 589,592
Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues									768,870	619,264	589,592
CAM [Member]
Segment Reporting Information [Line Items]
Non-lease external revenue									17,400	12,600	11,500
Customer revenues									195,092	177,789	166,303
CAM [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues									117,642	93,395	77,668
All other [Member]
Segment Reporting Information [Line Items]
Customer revenues									262,539	161,995	142,294
All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues									158,369	93,880	72,005
Aircraft maintenance and part sales [Member] | All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues									40,754	33,687	26,393
Mail handling services [Member] | All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues									103,191	47,307	34,025
Facility and ground equipment maintenance [Member] | All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues									12,709	11,490	11,119
Other [Member] | All other [Member] | Customer Revenues [Member]
Segment Reporting Information [Line Items]
Customer revenues									$ 1,715	$ 1,396	$ 468