Organization and Summary of Significant Accounting Policies - Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Changes in accumulated other comprehensive income (loss) by component
Beginning balance	$ 735,618	$ 684,928
Total other comprehensive income	4,707	1,440
Ending balance	737,873	675,298
Interest expense	22,547	21,421
Benefit from income taxes	(354)	(323)
Accumulated Other Comprehensive Income (Loss)
Changes in accumulated other comprehensive income (loss) by component
Beginning balance	1,197	(1,678)
Ending balance	3,194	(1,129)
Derivatives Cash Flow Hedges
Changes in accumulated other comprehensive income (loss) by component
Beginning balance	1,197	(1,678)
Loss recognized in other comprehensive loss, net of tax	1,572	236
Loss reclassified from accumulated other comprehensive loss, net of tax	425	313
Total other comprehensive income	1,997	549
Ending balance	3,194	(1,129)
Gain (loss) recognized in other comprehensive income (loss) related to change in fair value of derivative financial instruments before tax	2,000	300
Tax provision (benefit) of loss recognized in other comprehensive income (loss) related to change in fair value of derivative financial instruments	400	100
Derivatives Cash Flow Hedges \| Reclassification adjustments \| Interest rate swaps
Changes in accumulated other comprehensive income (loss) by component
Interest expense	200	500
Benefit from income taxes	$ 300	$ 200

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount after tax, before reclassification adjustments of other comprehensive income (loss).

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Amount of stockholders' equity (deficit), net of receivables from officers, directors, owners, and affiliates of the entity, attributable to both the parent and noncontrolling interests. Amount excludes temporary equity. Alternate caption for the concept is permanent equity.

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