Derivative Financial Instruments - Schedule of Derivatives (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Derivatives
Notional Amount	$ 513,208	$ 401,079
Fair Value, Asset	2,093	1,525
Fair Value, Liability	(2,474)	(69)
Change in fair value	(2,845)	1,127	$ (941)
Change in fair value of interest rate derivatives	(951)	1,127	(941)
Unrealized cash flow hedge losses	(1,894)	0	0
Interest rate swaps
Derivatives
Change in fair value	(2,281)	770	(795)
Interest rate caps
Derivatives
Total change in fair value	(564)	357	$ (146)
Not Designated as Hedging Instrument
Derivatives
Notional Amount	450,000	401,079
Fair Value, Asset	2,093	1,525
Fair Value, Liability	(749)	(69)
Not Designated as Hedging Instrument \| Interest rate swaps
Derivatives
Notional Amount	100,000	56,079
Fair Value, Asset	303	10
Fair Value, Liability	(749)	(69)
Not Designated as Hedging Instrument \| Interest rate caps
Derivatives
Notional Amount	350,000	345,000
Fair Value, Asset	1,790	1,515
Fair Value, Liability	0	0
Designated as Hedging Instrument \| Interest rate swaps
Derivatives
Notional Amount	63,208	0
Fair Value, Asset	0	0
Fair Value, Liability	$ (1,725)	$ 0

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

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Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount of increase (decrease) in the fair value of derivatives recognized in the income statement.

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Amount of realized and unrealized gain (loss) of derivative instruments not designated or qualifying as hedging instruments.

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Aggregate net gain (loss) on all derivative instruments recognized in earnings during the period, before tax effects.

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Amount before 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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