Financial Derivatives - Schedule of Derivative Instruments, Impact on Results of Operations (Details) - USD ($)
$ in Thousands |
12 Months Ended |
Dec. 31, 2015 |
Dec. 31, 2014 |
Dec. 31, 2013 |
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Gain (Loss) on Fair Value Hedges Recognized in Earnings |
$ (22,600)
|
$ (19,700)
|
$ (18,000)
|
| Gains/(losses) on financial derivatives and hedging activities |
2,531
|
(21,646)
|
31,764
|
| Designated as Hedging Instrument [Member] | Fair Value Hedging [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Change in Unrealized Gain (Loss) on Hedged Item in Fair Value Hedge |
3,100
|
14,520
|
(18,230)
|
| Gain (Loss) on Fair Value Hedges Recognized in Earnings |
9,065
|
11,791
|
11,308
|
| Not Designated as Hedging Instrument [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Gains/(losses) on financial derivatives and hedging activities |
(5,983)
|
(33,427)
|
20,495
|
| Interest Rate Swap [Member] | Fair Value Hedging [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Gain (Loss) on Components Included from Assessment of Interest Rate Fair Value Hedge Effectiveness |
9,200
|
11,600
|
11,800
|
| Gain (Loss) on Fair Value Hedge Ineffectiveness, Net |
100
|
(200)
|
500
|
| Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] | Fair Value Hedging [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Change in Unrealized Gain (Loss) on Fair Value Hedging Instruments |
5,965
|
(2,729)
|
29,538
|
| Interest Rate Swap [Member] | Designated as Hedging Instrument [Member] | Cash Flow Hedging [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Gain (Loss) on Interest Rate Cash Flow Hedge Ineffectiveness |
(551)
|
(10)
|
(39)
|
| Gain (Loss) on Cash Flow Hedge Ineffectiveness, Net |
(551)
|
(10)
|
(39)
|
| Interest Rate Swap [Member] | Not Designated as Hedging Instrument [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Gains/(losses) on financial derivatives and hedging activities |
(3,204)
|
(31,101)
|
21,394
|
| Forward Contracts [Member] | Not Designated as Hedging Instrument [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Gains/(losses) on financial derivatives and hedging activities |
(2,440)
|
(1,842)
|
(1,002)
|
| Future [Member] | Not Designated as Hedging Instrument [Member] |
|
|
|
| Derivative Instruments, Gain (Loss) [Line Items] |
|
|
|
| Gains/(losses) on financial derivatives and hedging activities |
$ (339)
|
$ (484)
|
$ 103
|