Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Article 12
-Section 13
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No definition available.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 30
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Fair value as of the balance sheet date of interest rate derivative assets, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as assets.

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Fair value as of the balance sheet date of interest rate derivative liabilities, which includes all such derivative instruments in hedging and nonhedging relationships that are recognized as liabilities.

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Number of interest rate derivative instruments held by the entity at the reporting date.

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Amount after tax of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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The net change in the difference between the fair value and the carrying value, or in the comparative fair values, of derivative instruments, including options, swaps, futures, and forward contracts, held at each balance sheet date, that was included in earnings for the period.

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Derivative and Hedging Activities Derivative and Hedging Activities (Details) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Jun. 30, 2018 USD ($)	Jun. 30, 2017 USD ($)	Feb. 09, 2018 USD ($)	Dec. 31, 2017 USD ($)
Derivative Instruments, Gain (Loss) [Line Items]
Interest Rate Derivative Assets, at Fair Value	$ 10,500		$ 10,500			$ 2,200
Interest Rate Cash Flow Hedge Gain (Loss) to be Reclassified During Next 12 Months, Net	700		700
Unrealized Gain on cash flow hedging activities	5,181	$ 0	8,782	$ 0
Derivative Instruments, Gain Recognized in Other Comprehensive Income (Loss), Effective Portion	5,200		8,800
Interest Rate Derivative Liabilities, at Fair Value	0		0			500
Interest Rate Cap [Member] \| Not Designated as Hedging Instrument [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount		$ 175,000		$ 175,000
Interest Rate Swap [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Interest Rate Derivative Assets, at Fair Value	10,500		10,500			2,200
Interest Rate Derivative Liabilities, at Fair Value	0		0			$ 500
Interest Rate Swap [Member] \| Designated as Hedging Instrument [Member] \| Cash Flow Hedging [Member]
Derivative Instruments, Gain (Loss) [Line Items]
Derivative, Notional Amount	$ 400,000		$ 400,000		$ 200,000
Number of Interest Rate Derivatives Held	5		5		2