Segment Reporting - Non-cash items (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Non cash items included in segment income (loss) from operations by reportable segment
Amortization of intangible assets	$ 25,694
Depreciation and amortization	54,543	$ 18,733	$ 17,817
Stock-based compensation	15,532	11,627	10,767
Segments \| Strayer University
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	19,997	18,268	17,380
Stock-based compensation	11,602	11,627	10,767
Segments \| Capella University
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	7,382
Stock-based compensation	1,495
Segments \| Non-Degree Programs
Non cash items included in segment income (loss) from operations by reportable segment
Depreciation and amortization	741	$ 465	$ 437
Stock-based compensation	193
Segment Reconciling Items
Non cash items included in segment income (loss) from operations by reportable segment
Merger costs	2,242
Amortization of intangible assets	25,694
Merger costs	$ 729

Depreciation and amortization expenses that are associated with a merger.

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+ References

No definition available.

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- Definition

Stock-based compensation expenses that are associated with a merger.

+ References

No definition available.

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- Definition

The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

+ References

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The current period expense charged against earnings on long-lived, physical assets not used in production, and which are not intended for resale, to allocate or recognize the cost of such assets over their useful lives; or to record the reduction in book value of an intangible asset over the benefit period of such asset; or to reflect consumption during the period of an asset that is not used in production.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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