What does the `end` property mean in the XBRL data?

Question

I'm trying to read some programmatic API data from EDGAR, and I'm having trouble understanding the end property. For example, when looking at AssetsCurrent:

"end": "2018-03-31",
"val": 206935000000,
"accn": "0001652044-18-000016",
"fy": 2018,
"fp": "Q1",
"form": "10-Q",
"filed": "2018-04-24",
"frame": "CY2018Q1I"

This would suggest end means the end of the period for which this form is filed, but there's another block like:

"end": "2017-12-31",
"val": 197295000000,
"accn": "0001652044-18-000035",
"fy": 2018,
"fp": "Q3",
"form": "10-Q",
"filed": "2018-10-26"

Which seems to contradict that. What does end mean in these filings?

Edit: these come from filings for Alphabet

Answer 1

First, just to clarify, in the companyfacts filing you are linking to, the two vals appear under Assets, not AssetsCurrent.

Second, and more importantly, the end refers not to the end of the period with respect to which the report was filed, but the end of the period in which the particular val (in this case, Assets) is reported, which sometimes (but not always) corresponds to the "current" period covered by the filing.

If you look at the filing referred to in the first block, Form 10-Q For the quarterly period ended March 31, 2018 (i.e., Q1 2018) (which can be inferred from the fy, fp and form keys in the block) and look in PART I. FINANCIAL INFORMATION, ITEM 1., FINANCIAL STATEMENTS, you will find in the CONSOLIDATED BALANCE SHEETS table, under Total Assets, $197,205 reported As of December 31, 2017 (the end in the 2nd block) and $206,935 as March 31, 2018 (the end in the first block, which is also the "current" period for which this particular filing is made). These two amounts correspond to the two vals in the two blocks in your question.

Hopefully this isn't too confusing, but the bottom line is that the two blocks are consistent.

Answer 2

I think I understand it. The main idea is that a given filing contains data from previous periods. These numbers are also shown in the API as part of the filing. Look at the Q3 2018 report: https://www.sec.gov/Archives/edgar/data/1652044/000165204418000035/goog10-qq32018.htm The Q3 report for 2018 shows 197,295 in Assets for Dec 31, 2017. This is the meaning of the block that's confusing you:

"end": "2017-12-31", "val": 197295000000, "accn": "0001652044-18-000035", "fy": 2018, "fp": "Q3", "form": "10-Q", "filed": "2018-10-26"

Does this help? I am also analyzing EDGAR data and these details are buried in the documentation.