Debt (Debt With A Contractual Term Greater Than One Year) (Details) - USD ($)	Jan. 05, 2016	Dec. 31, 2015	Dec. 31, 2014
Debt Instrument [Line Items]
Gross long-term debt		$ 5,689,008,000	$ 4,772,843,000
Long-term Debt, Current Maturities		(843,620,000)	(1,011,315,000)
Long-term debt		4,845,388,000	3,761,528,000
Asset-Backed U.S. Commercial Paper Conduit Facility VIE [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		153,839,000	166,912,000
Term Asset-Backed Securitization VIEs [Member] | Secured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		1,463,154,000	1,271,533,000
Long-term Debt, Current Maturities		(353,400,000)	(366,900,000)
Medium-Term Notes Due 2015 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 600,000,000
Weighted average interest rate of asset-backed securitization transactions		1.15%
Medium-Term Notes Due 2015 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 0	599,817,000
Medium-Term Notes Due 2016 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 450,000,000
Weighted average interest rate of asset-backed securitization transactions		3.88%
Medium-Term Notes Due 2016 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 449,991,000	449,937,000
Medium-Term Notes Due 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 400,000,000
Weighted average interest rate of asset-backed securitization transactions		2.70%
Medium-Term Notes Due 2017 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 399,980,000	399,963,000
Medium-Term Notes Due 2017 1.55 rate [Member] [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 400,000,000
Weighted average interest rate of asset-backed securitization transactions		1.55%
Medium-Term Notes Due 2017 1.55 rate [Member] [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 399,650,000	399,464,000
Medium-Term Notes Due 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 888,000,000
Weighted average interest rate of asset-backed securitization transactions		6.80%
Medium-Term Notes Due 2018 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 878,308,000	887,381,000
Medium-Term Notes Due 2019 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 600,000,000
Weighted average interest rate of asset-backed securitization transactions		2.40%
Medium-Term Notes Due 2019 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 598,296,000	597,836,000
Medium-Term Notes Due 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 600,000,000
Weighted average interest rate of asset-backed securitization transactions		2.15%
Medium-Term Notes Due 2020 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 598,856,000	0
Senior Unsecured Notes due 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 450,000,000
Weighted average interest rate of asset-backed securitization transactions		3.50%
Senior Unsecured Notes due 2025 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 447,608,000	0
Senior Unsecured Notes due 2045 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount		$ 300,000,000
Weighted average interest rate of asset-backed securitization transactions		4.625%
Senior Unsecured Notes due 2045 [Member] | Unsecured Debt [Member]
Debt Instrument [Line Items]
Gross long-term debt		$ 299,326,000	$ 0
Financial Services Segment [Member] | Subsequent Event [Member] | Medium Term Notes due 2019 2.25 rate [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 600,000,000
Weighted average interest rate of asset-backed securitization transactions	2.25%
Financial Services Segment [Member] | Subsequent Event [Member] | Medium-Term Notes Due 2021 [Member]
Debt Instrument [Line Items]
Debt Instrument, Face Amount	$ 600,000,000
Weighted average interest rate of asset-backed securitization transactions	2.85%