Variable Interest Entities (Details) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Dec. 31, 2012 Term_Loan Entity Aircraft Subsidiary	Dec. 31, 2011 Term_Loan
Variable Interest Entity [Line Items]
Number of VIE's consolidated	9
Number of Aircrafts	22
Number of subsidiaries in securitization no.2	2
Percentage of common shares owned	95.00%
Limitation of trust risk to annual dividend	$ 2
Number of Irish Variable Interest Entities	2
Number of aircraft transferred to historical cost basis	12
Combined assets	$ 351,360
Elimination of class E-1 securities by consolidation	72,068
Variable Interest Entity, Consolidated, Carrying Amount, Liabilities	320,030
Type of term loans	11
Period of term loan	12 years
Number of new airbuses	11
Number of VIE ECA Loans Repaid		1
Number of outstanding term loan	10
Net book value of flight equipment held for lease	827,762
Consolidated debt outstanding	$ 652,916