COMMITMENTS AND CONTINGENCIES - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	6 Months Ended	1 Months Ended		6 Months Ended	12 Months Ended	6 Months Ended
	Jun. 30, 2013 Cases	Jun. 30, 2013 Minimum [Member]	Jun. 30, 2013 Maximum [Member]	Jun. 30, 2013 Heavy Transport Aircraft [Member]	Dec. 31, 2012 Heavy Transport Aircraft [Member] Aircraft	Jun. 30, 2013 Air Medical [Member] Aircraft	Jun. 30, 2013 2013 [Member]	Jun. 30, 2013 2014 [Member]	Jun. 30, 2013 2016 [Member]	Jun. 30, 2013 2017 [Member]	Jun. 30, 2013 2019 [Member]
Long-term Purchase Commitment [Line Items]
Number of aircrafts acquire under contract					6	6
Aggregate acquisition cost related to aircraft				$ 80.1		$ 15.1
Total aircraft deposits	9.2
Aggregate purchase price for aircraft							30.8	114.4	33.5	89.8	19.5
Aggregate estimated probable liability environmental matters	0.2
Period of initial work	21 days
Number of other suits between the parties involved for pending case	2
Expected term for decision following oral argument		20 days	60 days
Aggregate commitments under operating leases	245.7
Operational lease payable at Dec 31,2013	22.8
Lease commitment for aircraft	226.5
Facility lease commitments	$ 19.2