Property and Equipment (Narrative) (Details) (Flight Equipment [Member], USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014
CAM [Member]
Property, Plant and Equipment [Line Items]
Leased aircraft, carrying value	$ 298.7	$ 289.5
Boeing 727 and DC-8 aircraft and flight equipment [Member]
Property, Plant and Equipment [Line Items]
Disposal Group, Including Discontinued Operation, Property, Plant and Equipment	$ 0.7	$ 0.7

Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

Name:	us-gaap_DisposalGroupIncludingDiscontinuedOperationPropertyPlantAndEquipment
Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant