Consolidated Statements of Cash Flows (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
	Jun. 30, 2020	Jun. 30, 2020	Jun. 30, 2019
Statement of Cash Flows [Abstract]
Net income (loss)	$ (190,977)	$ (225,198)	$ 65,922
Adjustments to reconcile net income (loss) to net cash and restricted cash provided by operating activities:
Depreciation	88,117	177,822	174,313
Amortization of deferred financing costs		6,840	6,958
Amortization of lease premiums, discounts and incentives	6,404	12,100	11,056
Deferred income taxes		1,479	7,957
Non-cash share-based payment expense	0	38,727	5,903
Cash flow hedges reclassified into earnings	0	0	184
Proceeds from Collection of Finance Receivables		11,861	10,971
Security deposits and maintenance payments included in earnings		(129,349)	(24,162)
Gain on sale of flight equipment	279	(26,770)	(12,348)
Gain (Loss) on Extinguishment of Debt	(65)	(4,020)	0
Impairment of flight equipment	280,088	342,745	7,404
Provision for Loan and Lease Losses	1,206	4,801	0
Other		(1,300)	393
Changes in certain assets and liabilities:
Accounts receivable		(54,404)	(7,899)
Other assets		(52,990)	3,582
Accounts payable, accrued expenses and other liabilities		(13,981)	(11,619)
Lease rentals received in advance		(33,064)	7,181
Net cash and restricted cash provided by operating activities		63,339	245,612
Cash flows from investing activities:
Acquisition and improvement of flight equipment		(52,419)	(660,723)
Proceeds from sale of flight equipment		155,560	56,924
Aircraft purchase deposits and progress payments, net of returned deposits and aircraft sales deposits		(10,212)	18,054
Other		(508)	2,241
Net cash and restricted cash provided by (used in) investing activities		92,421	(591,055)
Cash flows from financing activities:
Repurchase of shares		(27,906)	(14,288)
Proceeds from Contributions from Parent		25,536	0
Proceeds from secured and unsecured debt financings		650,000	1,841,848
Repayments of secured and unsecured debt financings		(608,189)	(1,105,353)
Payment for Debt Extinguishment or Debt Prepayment Cost		2,750	0
Deferred financing costs		0	(12,165)
Security deposits and maintenance payments received		49,824	92,514
Security deposits and maintenance payments returned		(49,307)	(64,788)
Dividends paid		(24,025)	(45,054)
Net cash and restricted cash provided by financing activities		13,183	692,714
Net increase in cash and restricted cash:		168,943	347,271
Cash and restricted cash at beginning of period		155,443	167,853
Cash and restricted cash at end of period	324,386	324,386	515,124
Unrestricted and restricted cash and cash equivalents	$ 324,386	324,386	515,124
Supplemental disclosures of cash flow information:
Cash paid for interest		116,546	121,523
Cash paid for income taxes		144	115
Supplemental disclosures of non-cash investing activities:
Advance lease rentals, security deposits, maintenance payments, other liabilities and other assets assumed in asset acquisitions		37,742	35,889
Advance lease rentals, security deposits, maintenance payments, other liabilities and other assets settled in sale of flight equipment		16,480	10,938
Transfers from flight equipment held for lease to Net investment in leases and Other assets		28,916	59,185
Payments to Acquire Interest in Subsidiaries and Affiliates		$ 0	$ 7,551